Immune System

These ingredients are often used in alternative medicine to support immune system.

• 2'-fucosyllactoseScientific

  2'-FL exerts broad immunomodulatory effects, including modulation of T-cell subsets, NK cell activity, cytokine production, and secretory immunoglobulin levels. A randomized controlled trial in infants found that those fed formula containing 2'-FL had lower inflammatory cytokines, similar to breastfed infants. In a cyclophosphamide-immunosuppressed mouse model, 2'-FL significantly increased IL-10 and IFN-γ and showed a trend toward restored NK cell activity. In vitro studies on human mononuclear cells have shown dose-dependent immunomodulation.

• 7-keto-DHEAScientific

  In vitro human evidence shows that 7-Keto-DHEA augments interleukin-2 (IL-2) production in human lymphocytes, supporting immune cell activation. Preclinical studies further demonstrate immunomodulatory effects including restoration of Th1 responses, limitation of Treg expansion, and enhancement of macrophage antimicrobial activity. Human clinical trial data for immune outcomes remain sparse.

• abies spectabilisScientific

  Phytochemical analysis confirms the presence of flavonoids, alkaloids, coumarins, tannins, and naphthoquinones—established immunomodulatory classes—in A. spectabilis extracts. The 2021 review lists antibacterial and antifungal activity as in vitro–confirmed, and the 2026 study identifies immunomodulatory properties via TNF-α and COX pathway modulation.

• acaciaScientific

  Acacia gum modulates the immune system through SCFA-mediated suppression of pro-inflammatory cytokines (TNF-α, IL-6, CRP) and upregulation of antioxidant defenses. Human trials in RA, sickle cell anemia, and haemodialysis populations demonstrate significant reductions in inflammatory markers. Prebiotic modulation of gut microbiota also indirectly supports mucosal immune function.

• acai berryScientific

  Acai berry demonstrates immunomodulatory activity through its antioxidant and anti-inflammatory effects. Human studies show it reduces oxidative stress markers and modulates specific cytokines (IFN-γ). Preclinical data show acai modulates NF-κB and Nrf2 pathways central to immune regulation. NCCIH notes acai has been used in folk medicine for infectious diseases.

• acemannanScientific

  Acemannan is a well-characterized immunostimulant that activates macrophages, dendritic cells, and T cells, driving both innate and adaptive immune responses. It enhances phagocytosis, cytokine production, and interferon release. Human clinical data include monocytosis in response to oral administration and improved immune parameters in AIDS patients.

• adzuki beanScientific

  Adzuki bean bioactive peptides inhibit pro-inflammatory cytokines (TNF-α, IL-6), while its polyphenols modulate macrophage polarization from M1 to M2. The human T2D RCT found significant reductions in hs-CRP, TNF-α, and IL-6. Gut microbiota modulation by adzuki bean fiber also supports mucosal immune homeostasis.

• agrimonyScientific

  Agrimony displays documented immunomodulatory properties in multiple in vitro and in vivo studies: it decreases pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) while increasing anti-inflammatory cytokines, inhibits TLR-4 signalling, and demonstrates antiviral activity. These findings are preclinical; no human immunology RCT exists.

• AHCCScientific

  AHCC (Active Hexose Correlated Compound) is a standardized extract of cultured Lentinula edodes (shiitake) mycelia, primarily composed of acetylated alpha-glucan oligosaccharides, with documented immunomodulatory activity in multiple human clinical trials. It has been shown to enhance natural killer (NK) cell activity, promote CD4+ and CD8+ T-cell activation, and modulate interferon signaling. The most rigorous evidence to date is a phase II randomized, double-blind, placebo-controlled trial demonstrating significantly higher clearance of persistent high-risk HPV infections at a dose of 3 g/day. Mechanistic and clinical evidence together support classifying this relationship as scientific.

• ajoeneScientific

  Ajoene modulates immune cell function at multiple levels: it inhibits human lymphocyte proliferation, partially suppresses macrophage TNF-α and iNOS production, and enhances macrophage antimycobacterial activity. These are documented primarily in in vitro and cell culture models using human immune cells.

• ajwainScientific

  Ajwain's broad-spectrum antimicrobial activity (antibacterial, antifungal, antiviral, antiparasitic) documented in in vitro and animal studies constitutes scientific evidence for immune-relevant activity. Antioxidant and anti-inflammatory properties further support immune modulation.

• AKG (alpha-ketoglutarate)Scientific

  AKG modulates immune function by affecting epigenetic regulation of immune cells, acting as a precursor for glutamine (the primary fuel for lymphocytes and macrophages), and suppressing NF-κB-mediated inflammatory signaling. Clinical evidence in malnourished and surgical patients shows AKG-related improvements in immune markers. The 2022 Gyanwali review (Trends Endocrinol Metab) explicitly identifies AKG as affecting immune regulation.

• akkermansia muciniphilaScientific

  A. muciniphila is a well-documented gut immune modulator, enhancing barrier integrity to reduce antigen translocation, inducing regulatory T-cells, promoting anti-inflammatory M2 macrophage polarization, and suppressing pro-inflammatory cytokines (IL-1β, IL-6, TNF-α) via its outer membrane protein Amuc_1100 and extracellular vesicles. It sustains immune homeostasis and is inversely correlated with multiple immune-dysregulation diseases in humans.

• ALA (alpha-linolenic acid)Scientific

  ALA modulates innate and adaptive immune responses by regulating T-cell activity, cytokine production, and eicosanoid synthesis. It acts as a PPAR ligand to influence immune cell function and inflammation, and modulates Th1/Th2/Th17 balance.

• ALA (alpha-lipoic acid)Scientific

  ALA modulates both adaptive and innate immune system components. It suppresses pro-inflammatory NF-κB signaling, inhibits T cell activation and cytokine production (IFN-γ, IL-2), promotes anti-inflammatory mediators (IL-10, TGF-β), and modifies macrophage, NK cell, and B cell behavior.

• alfalfaScientific

  Alfalfa contains L-canavanine and other phytochemicals with documented immune-modulating effects. Animal studies demonstrate immunostimulatory effects; some human case reports show immune stimulation that can worsen autoimmune disease. This creates a scientifically documented but complex relationship with the immune system.

• algal oilScientific

  DHA and EPA from algal oil modulate immune function by reducing production of pro-inflammatory cytokines and shifting eicosanoid pathways toward less inflammatory mediators. These effects are documented in clinical studies measuring TNF-α, IL-1β, IL-6, and CRP. However, very high doses (>5 g/day) may suppress immune function, according to FDA guidance.

• alginic acidScientific

  Alginic acid and its oligosaccharide derivatives demonstrate immunomodulatory activity in preclinical models, including regulation of cytokine production, NF-κB inhibition, and enhancement of immune cell activity. Water-soluble alginic acid has shown immunopotentiating effects in tumor-bearing animal models.

• allspiceScientific

  Allspice demonstrates broad antimicrobial activity against bacteria and fungi in vitro, and its polyphenols modulate immune cytokine responses in cell models. A fish immunology study showed allspice supplementation improved innate immune parameters. Eugenol modulates macrophage inflammatory responses.

• almondScientific

  Almonds support immune function through their prebiotic effects on gut microbiota (which is central to immune regulation), vitamin E's role in T-cell function and antiviral defense, and polyphenols' anti-inflammatory and antimicrobial properties. RCT evidence shows suppression of pathogenic gut bacteria and modulation of inflammatory cytokines.

• aloe veraScientific

  Acemannan, aloe vera's primary polysaccharide, has documented immunomodulatory properties: it stimulates macrophage and dendritic cell activity via mannose receptor agonism, promotes M2 polarization, and has demonstrated immunopotentiating effects in animal studies. Oral aloe gel has been shown to stimulate cell-mediated immunity and antibody production in murine models.

• alpha-caroteneScientific

  Alpha-carotene contributes to immune function indirectly through its conversion to vitamin A (retinol), which is well-established as essential for immune response, epithelial integrity, and regulation of immune genes. NIH and clinical pharmacology sources confirm that vitamin A metabolites are critical for immune function and cellular differentiation. Vitamin A deficiency—preventable in part by adequate provitamin A carotenoid intake including alpha-carotene—is associated with impaired immunity and increased infectious disease mortality.

• alpha-glycosyl isoquercitrinScientific

  AGIQ is a mast cell stabilizer that inhibits IgE-mediated degranulation and histamine release, and suppresses pro-inflammatory cytokine production via NF-κB inhibition. Two human double-blind RCTs in pollinosis subjects showed significant improvement in immune-mediated ocular allergy symptoms. Preclinical evidence includes anti-anaphylactic cardiovascular protection.

• alpinia galangalScientific

  A. galanga modulates immune function via inhibition of pro-inflammatory cytokines (TNF-α, IL-1β, IL-4), upregulation of IL-2, and antimicrobial activity against a broad spectrum of pathogens. ACA modulates T-cell cytokine profiles. These effects are established in preclinical immunological models.

• amaranthScientific

  Amaranth has been shown to stimulate immune function through multiple phytochemical components including squalene, flavonoids, and zinc. It inhibited immunoglobulin E production in an animal study, relevant to allergic immune responses. Comprehensive reviews cite immunostimulatory activity as a documented health benefit of amaranth grain.

• anchoviesScientific

  Anchovies supply EPA, DHA, selenium, iron, vitamin D, and zinc — all of which have established roles in immune regulation. Selenium is an antioxidant cofactor for immune cell function, and omega-3s modulate innate immune responses by reducing pro-inflammatory cytokine production. Iron is required for lymphocyte proliferation and immune cell activity.

• andrographisScientific

  Andrographis paniculata has substantial clinical and mechanistic evidence supporting immune system modulation. Its primary bioactive, andrographolide, suppresses pro-inflammatory cytokines via NF-κB/MAPK pathway inhibition while stimulating innate immune cells such as NK cells and macrophages. Multiple RCTs and at least two systematic reviews confirm statistically significant reductions in the severity and duration of upper respiratory tract infection (URTI) symptoms. The herb also has a long documented history in Ayurvedic and Traditional Chinese Medicine for infections and fever.

• andrographolideScientific

  Andrographolide, the primary bioactive labdane diterpene from Andrographis paniculata, has well-documented immunomodulatory activity supported by both human clinical trials and mechanistic research. It suppresses pro-inflammatory signalling via NF-κB, JAK/STAT, and MAPK pathways, reducing cytokines such as TNF-α, IL-6, and IL-1β. Multiple randomised controlled trials and at least two systematic reviews demonstrate efficacy in reducing the severity and duration of uncomplicated upper respiratory tract infections (URTIs). Traditional use in Ayurvedic and Traditional Chinese Medicine for fever and respiratory illness aligns with this clinical evidence.

• anemarrhena asphodeloidesScientific

  Anemarrhena constituents modulate immune function through NF-κB and TLR4 inhibition, suppression of pro-inflammatory cytokines (IL-1, IL-6, TNF-α), and anti-platelet activity. Timosaponin AIII also influences macrophage polarization and neutrophil infiltration, demonstrating multi-level immunomodulatory activity.

• aniseScientific

  Anise has documented antimicrobial, antiviral, antifungal, and antioxidant properties that interact with immune defense mechanisms, recognized in the PMC pharmacological review. Aniseed extracts inhibit multidrug-resistant bacteria and show antioxidant activity exceeding vitamin C. Traditional use for infections and immune support is widespread.

• annattoScientific

  Annatto's bixin activates Nrf2-mediated antioxidant gene expression, downregulates NLRP3 inflammasome components, and its tocotrienols suppress NF-κB-driven pro-inflammatory cytokine production. Human clinical trials show annatto tocotrienol reduces CRP, TNF-α, IL-6, and IL-2, with immunological cytokines down-regulated 39–64% at 250 mg/day.

• appleScientific

  Apple polyphenols modulate immune function through anti-inflammatory mechanisms, gut microbiota modulation, and direct immunomodulatory effects on circulating immune cells. A human RCT demonstrated that apple consumption changed peripheral blood mononuclear cell gene expression alongside gut microbiota composition.

• apple cider vinegarScientific

  ACV demonstrates in vitro antimicrobial activity against multiple pathogens including E. coli, S. aureus, and C. albicans, suggesting immune-supportive antimicrobial properties. It also downregulates pro-inflammatory cytokine expression in cell studies. A 2023 meta-analysis of RCTs examined its effects on inflammation and oxidative stress as immune-relevant markers.

• apricotScientific

  Apricots provide vitamins A, C, and E—all established immunonutrients. Vitamin A maintains mucosal barrier integrity; vitamin C supports innate immune cell function and antibody production; polyphenols modulate immune-inflammatory responses. Multiple nutritional authorities and reviews cite apricot's antioxidant and immunomodulatory properties as contributing to immune defense.

• arabinogalactanScientific

  Larch arabinogalactan (LA), a high-molecular-weight polysaccharide from Larix spp., has been evaluated in multiple randomized, double-blind, placebo-controlled human trials for immune support. Clinical evidence shows it can reduce the incidence of common cold episodes and enhance antibody responses to certain vaccines. In cell and animal models it enhances natural killer cell activity, macrophage function, and pro-inflammatory cytokine secretion, though the precise mechanism in humans remains incompletely characterized.

• aronia melanocarpaScientific

  Aronia melanocarpa modulates immune function through suppression of NF-κB, reduction of pro-inflammatory cytokines (TNF-α, IL-6, CRP), elevation of anti-inflammatory IL-10, and inhibition of viral replication. A systematic review of RCTs confirmed significant effects on human inflammation biomarkers and antioxidant enzyme systems involved in immune regulation.

• ascorbyl palmitateScientific

  Ascorbyl palmitate modulates innate immune function through potent inhibition of the NLRP3 inflammasome, a key innate immune sensor that drives sterile inflammation and contributes to multiple chronic inflammatory diseases. In preclinical models, AP attenuated LPS-induced systemic inflammation, colitis, and autoimmune encephalomyelitis. This mechanism is more potent and specific than that of ascorbic acid.

• ashitabaScientific

  Ashitaba chalcones suppress NF-κB-driven inflammatory signaling and reduce TNF-α in animal models, modulating innate immune responses. Preclinical studies document antimicrobial and antiviral activity of ashitaba extracts. Traditional Japanese use included the herb as an immune tonic and blood purifier.

• ashwagandhaScientific

  Ashwagandha is well-documented as an immunomodulator, affecting both innate and adaptive immune arms. Clinical and preclinical evidence shows it boosts NK cell activity, regulates T- and B-cell responses, and modulates cytokine levels. A 2025 PMC review confirmed its immunomodulatory properties, and human RCTs have measured immunological endpoints.

• asparagusScientific

  A. racemosus possesses well-documented immunomodulatory activity, confirmed in preclinical studies and acknowledged in Ayurvedic pharmacopoeias. Water and alcohol-based extracts act as immunity boosters. Prebiotic inulin-FOS from asparagus stimulates immune cell signaling via gut microbiota. Anti-inflammatory effects on macrophage/cytokine pathways have been demonstrated.

• aspergillusScientific

  Aspergillus-derived enzymes (principally AN-PEP) reduce the immunogenic peptide load reaching the intestinal immune system by degrading gluten into non-immunogenic fragments before duodenal exposure. Clinical RCTs confirm significant reduction of immunogenic gluten epitopes in gluten-sensitive subjects. A. oryzae administration in murine models also suppressed pro-inflammatory cytokines (IL-6, IL-1β) in DSS-induced colitis.

• assam indigoScientific

  S. cusia alkaloids modulate multiple immune pathways—suppressing Th17/IL-17 axis, modulating NF-κB, regulating AHR-Th17/Treg balance, and exhibiting antiviral and antibacterial activity. Clinical evidence from UC and psoriasis trials confirms immunomodulatory effects in vivo in humans.

• astaxanthinScientific

  Astaxanthin, a xanthophyll carotenoid, has demonstrated immunomodulatory effects in human clinical trials, including enhanced NK cell cytotoxic activity, increased T and B lymphocyte counts, stimulated lymphoproliferation, and reduced inflammatory markers such as CRP, IL-6, and TNF-α. A 2025 systematic review of 15 human studies confirmed that astaxanthin consistently reduced pro-inflammatory cytokines and improved immune recovery, particularly when combined with exercise. Mechanistically, it acts via the NF-κB, Nrf2, and MAPK pathways, and by neutralizing reactive oxygen species to protect immune cells from oxidative damage. Evidence strength is moderate; most trials are small and further well-designed studies are needed.

• aster rootScientific

  Aster root peptides and polysaccharides exhibit documented immunomodulatory activity. Cyclic peptides including astin C can induce T-cell apoptosis and immunosuppressive effects. Separately, immunostimulatory effects have been documented for water extracts via mitogen-activated pathways. Both immunosuppressive and immunostimulatory properties have been reported, reflecting dual activity depending on preparation.

• astragalusScientific

  Astragalus membranaceus (Huang Qi) has documented use in Traditional Chinese Medicine as an immune tonic, and this is now supported by human clinical evidence. A 2023 systematic review and meta-analysis of 19 human studies found that astragalus enhanced immune responses and reduced proinflammatory cytokines. Its primary active constituents — polysaccharides (APS) and astragalosides — modulate T-cell activity, NK cells, macrophages, and cytokine profiles. Evidence quality across trials is generally rated low-to-moderate, with substantial heterogeneity noted.

• atractylodesScientific

  Immunomodulation is one of the most extensively documented pharmacological properties of Atractylodes macrocephala polysaccharides. They activate macrophages, stimulate lymphocyte and cytokine production, and increase spleen and thymus weights in preclinical models. This aligns with the TCM concept of tonifying Qi.

• bacillus clausiiScientific

  B. clausii exerts documented immunomodulatory effects in humans including stimulation of IFN-γ, IL-12, TGF-β, IL-10, and secretory IgA, while reducing pro-inflammatory and Th2 cytokines. Clinical studies have demonstrated these effects in children with respiratory infections and allergic rhinitis, and in children with persistent diarrhea. Proposed mechanisms include NF-κB pathway modulation and NLRP3 inflammasome suppression.

• bacillus coagulansScientific

  A double-blind, placebo-controlled RCT (n=50, 12 weeks) with B. coagulans SNZ 1969 demonstrated a 42.07% net increase in NK cell activity vs. placebo (p=0.0002), a 25% increase in serum IgA (p=0.0016), and a 27.7% increase in salivary IgA (p=0.0002). B. coagulans exerts immunomodulatory effects through gut-associated lymphoid tissue interactions.

• baikal skullcapScientific

  S. baicalensis flavonoids modulate both innate and adaptive immunity via toll-like receptor downregulation, NF-κB/MAPK pathway inhibition, macrophage polarization, Nrf2 activation, and cytokine regulation. This immunomodulatory profile has been confirmed in multiple in vitro and in vivo systems.

• bambooScientific

  Bamboo flavonoids and fiber modulate immune function through anti-inflammatory cytokine suppression (IL-6, TNF-α, MCP-1), gut microbiota regulation, and SCFA production. A 2025 ScienceDirect review specifically documents bamboo's immunomodulatory effects. TCM classifies bamboo as an immune-relevant herb with 'inhibit allergy reactions' and anti-inflammatory key actions.

• bananaScientific

  Banana antioxidants (vitamin C, polyphenols, dopamine) and anti-inflammatory compounds support immune function. Exercise RCTs demonstrated that banana metabolites inhibit COX-2 mRNA expression in monocytes, reducing exercise-induced inflammation. Banana's prebiotic resistant starch supports gut-associated immune function through microbiome modulation.

• baobabScientific

  Baobab's immune system relevance is primarily driven by its exceptional vitamin C content (>100 mg/100 g dried pulp), a micronutrient with well-established roles in immune cell function, neutrophil chemotaxis, and antiviral defense. Its polyphenol complex also contributes antioxidant protection of immune cells. In vitro studies have confirmed antimicrobial activity of baobab extracts against bacteria and fungi. Traditional use as a general tonic and immune-supporting preparation is documented across Africa.

• barberryScientific

  Barberry modulates the immune system through berberine's immunomodulatory effects, including increased T-helper cell production, modulation of cytokine profiles, and direct antimicrobial activity. Clinical evidence shows CRP reduction and anti-inflammatory cytokine changes. Traditional use as an immune-supportive herb is well-documented.

• barleyScientific

  Barley β-glucan is recognized as a biological response modifier that activates innate immune cells including macrophages and natural killer cells. Barley's SCFA-producing prebiotic activity also supports intestinal immune homeostasis. A systematic review of RCTs found evidence of immune modulation in clinical settings.

• barrenwortScientific

  Epimedium flavonoids, particularly icariin, are well-documented immunomodulators that suppress excessive inflammation via NF-κB, TLR4, and NLRP3 pathways while also synergistically inducing cytokines such as IL-2, IL-3, and IL-6. Multiple PMC reviews list immunomodulation as a core pharmacological activity of Epimedium. The herb has been used in TCM for immune-related chronic diseases.

• basilScientific

  O. basilicum has documented immunomodulatory effects including modulation of cytokines (TNF-α, IL-10, IL-4, IFN-γ), immunoglobulins (IgG, IgM, IgE), and innate immune mediators. A PMC review (2023) synthesized this evidence. Polysaccharide components show anti-tumor and immune-enhancing activity. Herbal Reality documents immune-regulatory and immune-enhancing effects.

• bee pollenScientific

  Bee pollen flavonoids modulate immune activity by activating B and T lymphocytes, exhibiting anti-allergic properties, and regulating inflammatory cytokines. Both immunostimulatory and immunomodulatory effects are documented in in vitro and clinical contexts. A ScienceDirect review confirmed clinical-level immune activation evidence.

• beetScientific

  Beetroot betalains modulate immune-related inflammatory pathways (NF-κB, COX-2) and provide antioxidant defense that supports immune cell function. In vitro and animal data are substantial; human RCT evidence for direct immune modulation is limited.

• belleric myrobalanScientific

  T. bellirica is documented in the ScienceDirect systematic review and pharmacological literature for immunomodulatory activity. Triphala (containing T. bellirica) is described in classical texts as exerting positive responses to the body against infectious conditions by acting on the immune system. In vitro studies demonstrate macrophage modulation, and the fruit's polyphenols suppress pro-inflammatory cytokines while maintaining antioxidant defense.

• benegut perillaScientific

  Perilla frutescens extract demonstrates immunomodulatory activity via inhibition of mast cell reactions, reduction of neutrophil and eosinophil infiltration in human subjects, and suppression of pro-inflammatory cytokines including TNF-α, IL-4, IL-5, and IL-8. A human RCT of rosmarinic acid-enriched Perilla extract showed significant reductions in nasal immune cell infiltration. Vicenin-2 in Benegut has been linked to decreased excitatory cytokines.

• berberineScientific

  Berberine demonstrates consistent immunomodulatory effects in both experimental models and clinical trials, inhibiting pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-17) and enhancing anti-inflammatory mediators (IL-10, TGF-β). It modulates macrophage activation and lymphocyte responses via AMPK and NF-κB pathways.

• beta and delta tocopherolsScientific

  Mixed tocopherol preparations including gamma and delta forms modulate innate and adaptive immune responses by reducing pro-inflammatory cytokine production in monocytes and suppressing inflammatory angiogenesis. A human clinical study showed that gamma-tocopherol-enriched supplementation (containing delta-tocopherol) decreased systemic oxidative stress and cytokine responses in monocytes of both healthy and asthmatic subjects. Tocopherols including delta forms inhibit VCAM-1 expression, relevant to immune cell trafficking.

• beta-caroteneScientific

  Beta-carotene enhances multiple arms of immunity including NK cell activity, T and B lymphocyte proliferation, macrophage function, and interleukin production, both through its provitamin A activity and through independent antioxidant mechanisms. Clinical trials in humans have demonstrated dose-dependent increases in NK cell markers and IL-2 receptor expression following supplementation. Retinoic acid derived from beta-carotene plays a key regulatory role in T cell differentiation, mucosal immunity, and regulatory T cell induction.

• beta-glucanScientific

  Beta-glucan is a well-characterized immunomodulatory polysaccharide with documented mechanisms of action in the human innate immune system, supported by multiple randomized controlled trials and meta-analyses. Its primary receptors—Dectin-1, complement receptor 3, and scavenger receptors—are expressed on neutrophils, macrophages, and dendritic cells, enabling activation of both innate and adaptive immune responses. Clinical evidence most consistently supports a reduction in upper respiratory tract infection incidence, duration, and severity. Some trials also show enhancement of T-lymphocyte and natural killer cell populations; however, not all human studies report positive immune outcomes, and effect sizes vary by source, dose, and formulation.

• beta-sitosterolScientific

  A human pilot RCT (Bouic et al., Int J Sports Med 1999) found that a BSS:BSSG mixture significantly reduced the cortisol:DHEAs ratio and post-marathon immune suppression, with increased CD3+ and CD4+ lymphocyte subsets and decreased IL-6 in treated marathon runners versus placebo. In vitro, BSS and its glucoside enhance T-cell proliferative responses to phytohaemagglutinin at femtogram concentrations. EFSA evaluated a health claim application for BSS:BSSG and normal immune function, concluding evidence was insufficient for a claim approval, indicating scientific interest but evidentiary limitations.

• betelScientific

  Piper betle leaf extracts display immunomodulatory properties, including enhancement of immune cell activity and antioxidant enzyme elevation. Weight of the spleen increased in treated animals in antidiabetic studies, suggesting lymphoproliferative activity. Antimicrobial activity against a wide range of pathogens also supports immune-relevant defense.

• bifidobacterium animalisScientific

  B. animalis subsp. lactis strains have demonstrated immune-modulating activity across multiple human clinical trials, including increased NK-cell cytotoxicity, elevated IL-2 and sIgA, cathelicidin upregulation, and improved resistance to upper respiratory and gastrointestinal infections. BB-12 specifically is described in over 130 human clinical studies with documented immune outcomes. HN019 supports immune defense by competing with and excluding pathogens in human studies.

• bifidobacterium bifidumScientific

  B. bifidum is among the most studied bifidobacterial species for immunomodulation. It interacts directly with innate and adaptive immune cells, modulates dendritic cell phenotypes, stimulates IgA production, and converts vitamin A to retinoic acid to support immunological tolerance. These effects have been documented in human cell studies, preclinical models, and human clinical trials.

• bifidobacterium breveScientific

  B. breve exerts well-characterized immunomodulatory effects, interacting with Toll-like receptors to regulate cytokine production, expand regulatory T and B cells, and improve gut barrier function. It promotes IL-10 and TGF-β while suppressing TNF-α, IL-6, and IL-1β, creating an anti-inflammatory immune environment. These properties underpin its studied benefits in allergic, inflammatory, and autoimmune-adjacent conditions.

• bifidobacterium lactisScientific

  Bifidobacterium lactis (particularly strains HN019 and BB-12) has substantial clinical evidence supporting immune modulation. Multiple randomized controlled trials and a systematic review/meta-analysis demonstrate enhanced innate immune cell activity—specifically increased polymorphonuclear (PMN) phagocytic capacity and natural killer (NK) cell tumoricidal activity—in healthy elderly adults. Additional RCT evidence shows reductions in allergic immune markers (total IgE, IL-13) and upregulation of immune activation gene expression in adults.

• bifidobacterium longumScientific

  B. longum is established as an immunomodulatory probiotic, suppressing pathogen invasion, regulating intestinal microecology, and affecting both innate and adaptive immune responses. In infants, Bifidobacterium accelerates immune maturation and balances the immune system to suppress excessive inflammation. Clinical trials show B. longum-containing formulas reduce allergic and infectious disease morbidity.

• bilberryScientific

  Bilberry anthocyanins modulate innate and adaptive immune responses, suppressing pro-inflammatory cytokine expression (TNF-α, IL-1β, IL-6, IFN-γ) and NF-κB signaling in human monocytic and macrophage cells. Clinical colon biopsy data from UC patients confirm immunomodulatory effects in vivo, and a clinical RCT in aged men showed reduced plasma inflammatory biomarkers.

• birchScientific

  Birch bark extracts (betulin, betulinic acid) have documented immunomodulatory and interferon-inducing activity in preclinical studies. Betulinic acid induces apoptosis of immune cells via mitochondrial pathways and has antiviral properties. Birch leaf flavonoids contribute antioxidant protection relevant to immune cell function. Evidence is predominantly preclinical.

• black cuminScientific

  Clinical and experimental studies confirm N. sativa modulates both innate and adaptive immunity: it enhances phagocytic activity, NK cell function, T-lymphocyte proliferation, and CD8 T-cell counts while reducing excessive inflammatory cytokine production. Clinical benefits are documented in allergic, autoimmune, and infectious conditions.

• black pepperScientific

  Piperine has documented immunomodulatory properties confirmed in clinical contexts: it modulates macrophage polarization, inhibits inflammatory cytokines, and clinical trials confirm immune marker changes. A pilot human study in hepatocellular carcinoma showed improved CD4/CD8 immunological marker ratios.

• black seedScientific

  Black seed (Nigella sativa) has documented immunomodulatory activity supported by multiple clinical trials and systematic reviews. Its primary bioactive compound, thymoquinone (TQ), modulates key inflammatory mediators and immune cell populations. Human RCT evidence demonstrates measurable effects on T-lymphocyte counts and cytokine profiles, though effect sizes vary by dose and population, and further large-scale trials are still needed.

• black spruceScientific

  Conifer phytoncides — the volatile organic compounds of which black spruce essential oil is composed — have been shown in multiple human studies to enhance natural killer (NK) cell activity and cytotoxic protein expression. Picea mariana bark polyphenols have also shown immunomodulatory effects in vitro.

• black teaScientific

  Black tea polyphenols modulate immune function by reducing pro-inflammatory cytokine expression, enhancing antimicrobial defenses via beta-defensin induction in mucosal cells, and modulating immune cell populations. Clinical trials suggest reductions in CRP and immune cell changes in metabolic disease contexts.

• black walnutScientific

  Black walnut extracts demonstrate immunomodulatory activity in preclinical studies, including modulation of pro-inflammatory cytokines in human cell lines, antimicrobial action against multiple pathogens, and antifungal effects. The Russian pharmacological review documents immunomodulatory activity in preclinical trials. Animal studies show walnut green husk significantly elevated immunoglobulin levels.

• blackberryScientific

  Blackberry provides vitamin C, vitamin E, and manganese—recognized immune-supporting micronutrients—and its polyphenols modulate innate immune inflammatory responses. Cell studies confirm blackberry anthocyanins suppress NF-κB and NLRP3 inflammasome activation, regulating immune cell signaling. Blackberry's antimicrobial ellagic acid and tannins further support mucosal immune defense.

• blackboard treeScientific

  A PMC-indexed study demonstrated that a combination of alkaloids and triterpenes from A. scholaris leaves enhanced immunomodulatory activity in C57BL/6 mice, modulating IL-6 and TNF-α levels. Immunostimulant and immunomodulatory properties have been confirmed in multiple preclinical studies.

• bladderwrackScientific

  Fucoidan from bladderwrack activates macrophages and dendritic cells, modulates NF-κB and TLR-mediated immune signaling, and exhibits antiviral and antibacterial activity in cell models. Prebiotic effects on gut microbiota further regulate immune homeostasis. Human data are limited but mechanistic evidence is strong.

• blueberryScientific

  Blueberry polyphenols modulate innate immune signaling by suppressing NF-κB activation and reducing pro-inflammatory cytokine production (TNF-α, IL-6, CRP). Human RCT data confirm reductions in circulating inflammatory markers in metabolic syndrome and diabetic populations.

• bonesetScientific

  Polysaccharide fractions of E. perfoliatum have demonstrated enhancement of phagocytosis in vitro (Wagner & Jurcic, 1991). A 2011 comprehensive in vitro study (Maas et al., J Ethnopharmacol) tested lymphocyte transformation and macrophage activation. While immunostimulating effects have not been consistently confirmed across all assays, anti-inflammatory modulation of innate immune cytokines is well-supported preclinically. No human immunological trials exist.

• borageScientific

  GLA from borage seed oil modulates immune function through eicosanoid pathways, reducing pro-inflammatory cytokines including IL-1β, TNF-α, and LTB4 in human studies. Borage oil also exhibits antimutagenic and potential chemopreventive effects relevant to immune defence. In vitro cytotoxic activity against promyelocytic leukaemia cells has been documented.

• borage oilScientific

  Borage oil's GLA directly modulates immune cell function by raising DGLA in immune cell membranes, suppressing LTB4, thromboxane, TNF-α, IL-1β, and PGE2 production, and acting on T lymphocytes independently of eicosanoid pathways. These immunomodulatory effects are supported by ex vivo, mechanistic, and controlled human studies.

• boronScientific

  Nielsen and Meacham (2011, SAGEPUB) listed modulation of immune response as a reported beneficial action of boron, alongside inflammation and oxidative stress modulation. Boron down-regulates inflammatory enzyme activity and modulates macrophage and immune cell responses to antigens, as documented in animal and limited human data.

• boswelliaScientific

  Boswellia serrata extracts modulate both innate and adaptive immune responses: inhibiting 5-LOX and NF-κB to reduce pro-inflammatory cytokines, while ex vivo data demonstrate influence on regulatory and effector T-cell compartments. These immunomodulatory effects underpin its observed benefits across asthma, IBD, and arthritis trials.

• bovine kidneyScientific

  Bovine kidney is a rich dietary source of selenium, which is essential for immune system function. Selenium supports both innate and adaptive immunity via selenoproteins, regulates cytokine responses, and modulates T-cell differentiation. Clinical and epidemiological evidence links selenium deficiency to impaired immune defense, and supplementation studies demonstrate immune-relevant outcomes.

• bovine liverScientific

  Bovine liver provides vitamin A, zinc, copper, iron, and selenium — each recognized by the NIH and WHO as essential for specific arms of immune function. Vitamin A regulates the differentiation and activity of T-cells, B-cells, and NK cells. Zinc and copper modulate inflammatory responses and immune cell proliferation.

• boxthorneScientific

  LBPs are established immunomodulatory agents that stimulate macrophages, NK cells, dendritic cells, and T-cell responses. Human studies in older adults confirm increased immune cell markers after standardized wolfberry juice consumption. Multiple clinical trials listed in human study reviews document immune support as a primary outcome of L. barbarum supplementation.

• broccoliScientific

  Sulforaphane from broccoli modulates innate immune function, reducing excessive macrophage-driven inflammation (through NF-κB inhibition and Nrf2 activation) while supporting the body's antioxidant defenses. Human cell studies and clinical trials document immunomodulatory effects including reduced inflammatory cytokines and CRP.

• bromelainScientific

  Bromelain exerts well-documented immunomodulatory effects: it modulates T cell surface adhesion molecules (CD44, CD62L), activates NK cells, alters CD4+/CD8+ T cell ratios, and modulates cytokine secretion. PMC evidence demonstrates both immune-stimulating and immune-regulating (anti-inflammatory) effects depending on context, consistent with its proposed use in inflammatory and autoimmune conditions.

• broomrapeScientific

  Orobanche cumana has traditionally been attributed immune-enhancing effects in ancient Chinese herbalism, and the phenylpropanoid glycosides of broomrape species are documented in the PubMed literature as showing 'immune system enhancing' properties. Preclinical pharmacodynamic studies of O. cumana extract support immunostimulating activity.

• brussel sproutsScientific

  Brussels sprouts provide very high levels of vitamin C (>100% DV/cup), a key antioxidant and immune cofactor, plus glucosinolate phytochemicals and vitamin A that collectively support innate and adaptive immune function. Vitamin C supports leukocyte function and barrier integrity.

• bupleurum falcatumScientific

  B. falcatum saikosaponins (especially D) and pectic polysaccharides (bupleuran 2IIc) exert immunomodulatory effects in vitro and in vivo, including T-lymphocyte regulation, B-cell activation, IL-2 upregulation, and complement inhibition. This bidirectional immunomodulation is among the herb's best-characterized pharmacological properties.

• burdockScientific

  Burdock root contains inulin-type fructooligosaccharides that modulate the gut microbiota, influencing immune education via the gut-associated lymphoid tissue. MSKCC notes that animal experiments showed burdock 'induced an immune response.' A ScienceDirect study on immunomodulatory effects of burdock inulin-type fructans found targeting of gut microbiota and metabolites as the mechanism.

• butterburScientific

  Butterbur's petasins modulate key immune-inflammatory mediators including leukotrienes, prostaglandins, and histamine. Clinical studies in allergic rhinitis demonstrate suppression of IgE-mediated type I hypersensitivity responses, comparable to antihistamine drugs. These immunomodulatory effects are well-characterized in peer-reviewed pharmacological and clinical literature.

• butyrate triglycerideScientific

  Butyrate delivered via tributyrin exerts broad immunomodulatory effects: inducing Treg cells, suppressing NF-κB-mediated cytokine production, reducing neutrophil pro-inflammatory signaling, and enhancing innate immunity via antimicrobial peptide induction. The 2025 in vitro CoreBiome tributyrin study demonstrated immunomodulatory effects in THP1 macrophage co-cultures. A 2024 human visceral fat study showed tributyrin significantly reduced LPS-induced cytokines in human tissue.

• butyric acidScientific

  Butyrate is a key regulator of intestinal immune homeostasis, inducing regulatory T-cells, suppressing pro-inflammatory cytokines, and maintaining the mucosal immune barrier. Its immunomodulatory effects have been demonstrated across multiple human clinical conditions including IBD and metabolic disease.

• cabbageScientific

  Cabbage is an excellent source of vitamin C, a well-established immune-supporting nutrient. Vitamin C supports innate and adaptive immune responses, stimulates white blood cell function, and acts as an antioxidant within immune cells. Indoles from cabbage also modulate intestinal immune function and inflammatory response.

• cabbage leafScientific

  Cabbage leaf contains glucosinolates, isothiocyanates, vitamin C, and flavonoids that modulate immune function. Glucosinolate-derived metabolites regulate intestinal immune responses, influence microbiota composition, and activate Nrf2-mediated antioxidant defense relevant to immune homeostasis. A 2024 PMC review found that cruciferous glucosinolates attenuate intestinal inflammation and restore intestinal barrier function, both critical to mucosal immune defense.

• caesalpinia cristaScientific

  Immunomodulatory activity of C. crista has been documented in preclinical studies, with effects on leukocyte counts, and the plant is listed among medicinal plants with immunomodulatory properties in multiple peer-reviewed reviews. Antiviral and adaptogenic activities further underscore systemic immune relevance.

• cajuputScientific

  M. cajuputi extracts have demonstrated immunomodulatory effects in animal models, including modulation of IL-6, IL-6R, and IL-10 in LPS-induced inflammation (Applied Biosciences, 2026). In vitro antimicrobial and antifungal activity support immune-relevant pathogen defence. An in silico study (PMC11620808) identified M. cajuputi compounds interacting with IL-6 inflammatory signalling pathways.

• calamari oilScientific

  EPA and DHA from calamari oil modulate immune function by reducing pro-inflammatory cytokine production (TNF-α, IL-1β, IL-6), generating pro-resolving mediators (resolvins, protectins), and altering immune cell membrane properties. These effects are documented in multiple human clinical studies and are relevant to chronic inflammatory and autoimmune conditions.

• calendulaScientific

  Calendula demonstrates immunomodulatory activity in vitro, including lymphocyte activation. Its polysaccharides and saponins enhance phagocytic activity. ESCOP lists immunomodulation among pharmacological properties. Indirect clinical evidence derives from studies in radiation mucositis and wound healing where immune-mediated inflammation is modulated.

• campesterolScientific

  Campesterol modulates immune function through downregulation of pro-inflammatory cytokines including TNF-α, IL-1, IL-6, and TGF-β in multiple in vitro and animal models. It reduces immune cell-mediated inflammation in arthritic, cystitis, and asthma models. Evidence is preclinical; human immunological data are limited.

• camu camuScientific

  Camu camu is among the richest known food sources of vitamin C, a nutrient with well-documented roles in innate and adaptive immunity including neutrophil chemotaxis, NK cell activity, lymphocyte proliferation, interferon production, and antibody synthesis. The 2008 human RCT showed superior reduction of inflammatory and oxidative immune markers versus vitamin C tablets. Traditional Amazonian use of camu camu for immune-related conditions is also well documented.

• caprylic acidScientific

  Caprylic acid has antimicrobial properties against Candida and selected bacteria relevant to mucosal immune defence. In vitro and animal data show MCTs reduce inflammatory cytokine production (IL-8, eicosanoids). Clinical nutrition use of MCT in immunocompromised populations (HIV, TPN patients) is documented. Direct human immunomodulation RCTs for caprylic acid alone are limited.

• capsaicinoidsScientific

  Capsaicin modulates immune function through NF-κB suppression, inhibition of pro-inflammatory cytokines, and suppression of inflammatory macrophage activity in adipose tissue. Antioxidant and anti-inflammatory properties contribute to immune regulation. Preclinical evidence is robust; human immunological data are emerging.

• capsanthinScientific

  Capsanthin modulates immune signaling by suppressing pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, MCP-1), inhibiting NF-κB, and upregulating anti-inflammatory IL-10-related pathways. As a xanthophyll, it shares immunomodulatory class properties demonstrated across preclinical models.

• capsicumScientific

  Capsaicin modulates immune function by suppressing NF-κB-driven inflammatory cytokine production, inhibiting COX-2, activating Nrf2 antioxidant pathways, and modulating innate immune cell activity. These effects translate to documented anti-inflammatory outcomes in human tissue studies.

• cardamomScientific

  Cardamom has documented immunomodulatory effects in clinical and laboratory studies, including significant reductions in pro-inflammatory cytokines (hs-CRP, IL-6, TNF-α) across multiple RCTs, antimicrobial activity against pathogens, and antioxidant protection of immune cells. Multiple peer-reviewed reviews list 'immunomodulatory' among cardamom's established pharmacological properties.

• caroteneScientific

  Beta-carotene supports innate and adaptive immune function both independently as an antioxidant and via its conversion to vitamin A, which regulates immune cell differentiation, mucosal immune defense, and T-cell function. Higher dietary carotenoid intake is associated with fewer respiratory infections and better immune outcomes. Beta-carotene is a normal component of breast milk contributing to neonatal immune defense.

• carrotScientific

  Beta-carotene modulates immune function by regulating leukocyte formation, enhancing immunoglobulin production, and modulating cytokine release. Human ex vivo studies show carrot juice intake alters cytokine and chemokine profiles in blood. A critical review confirms carrot bioactives have broad immunomodulatory activity.

• caryophylleneScientific

  BCP modulates immune function primarily through CB2 receptors expressed on immune cells, shifting macrophage and microglia polarization toward anti-inflammatory phenotypes and reducing pathological cytokine production. It also has documented antimicrobial activity.

• caseinScientific

  Casein hydrolysates and bioactive peptides derived from casein demonstrate antimicrobial and immunomodulatory properties in cell-based studies. Casein phosphopeptides have shown antibacterial activity and suppression of pro-inflammatory cytokines. Evidence in humans is limited, with most data from in vitro and preclinical models.

• cat's clawScientific

  Cat's Claw (Uncaria tomentosa) has documented immunomodulatory properties supported by preclinical and limited human evidence. Its key bioactive compounds—pentacyclic oxindole alkaloids and quinovic acid glycosides—modulate immune mediators including NF-κB and IL-6. The NIH/NCCIH acknowledges it may increase immune system activity, while a 2024 PROSPERO-registered meta-analysis confirmed significant reductions in IL-6 and NF-κB in animal models. Human clinical trials exist but are small and methodologically limited, so overall evidence strength remains moderate.

• catalaseScientific

  Catalase activity is measurably reduced in immune cells (erythrocytes and leukocytes) during active inflammatory and autoimmune diseases, including IBD, vitiligo, and rheumatoid arthritis. H₂O₂ produced during immune cell activation acts as a signaling molecule, and catalase modulates its concentration to regulate immune responses.

• catechinsScientific

  Catechins modulate both innate and adaptive immunity: they suppress pro-inflammatory cytokine production via NF-κB/TLR4 inhibition, exhibit direct antiviral and antibacterial activity, and enhance antioxidant immune defenses via Nrf2. An RCT in 270 healthcare workers showed catechin beverages reduced upper respiratory tract infection incidence.

• catjang cowpeaScientific

  Cowpea polyphenols have demonstrated anti-inflammatory activity in immune cell models, reducing ROS and inflammatory mediators in macrophage and colonic cell lines. The zinc content of catjang cowpea also supports immune function. Antimicrobial properties of leaf extracts are documented in vitro.

• cauliflowerScientific

  Sulforaphane modulates immune function via Nrf2 activation and NF-κB inhibition, reducing pro-inflammatory cytokine production. Vitamin C in cauliflower supports immune cell function. I3C and isothiocyanates show antimicrobial properties in preclinical studies.

• cayenne pepperScientific

  Cayenne pepper provides vitamins C and A (beta-carotene) with established immune-supporting roles, and capsaicin has demonstrated immunomodulatory effects including modulation of pro-inflammatory cytokines and gut microbiome composition (enriching Bifidobacterium). Cleveland Clinic confirms cayenne supports the gut microbiome, which is central to immune function.

• chaff flowerScientific

  Immunomodulatory activity of A. aspera is established through preclinical studies showing enhanced macrophage function, NK cell activation, T lymphocyte stimulation, and humoral immunity. ABPS (A. aspera polysaccharides) are the key immunoactive fraction.

• chamomileScientific

  A randomized triple-blind placebo-controlled RCT found chamomile syrup significantly increased absolute neutrophil count (ANC) in pediatric leukemia patients undergoing chemotherapy, reversing neutropenia trends. Chamomile flavonoids modulate T-cell driven immune responses, reducing hyperactive inflammation while supporting immune resolution. A systematic review confirmed chamomile as a recognized immunomodulatory agent.

• champignonScientific

  Beta-glucans from Agaricus bisporus have been shown to drive Trained Immunity in human monocytes and macrophages in vitro and in vivo, enhancing non-specific innate immune responses. Separately, A. bisporus polysaccharides stimulate pro-inflammatory cytokine production in human monocytic THP-1 cells. The extract also attenuates excessive innate immune signaling (NF-κB) in both mouse and human macrophages, indicating dual immunomodulatory activity.

• chen piScientific

  Chen Pi's flavonoids modulate innate and adaptive immunity by suppressing NF-κB-mediated cytokine production, inhibiting IgE-mediated allergic responses, reducing Th2 cytokines, and activating Nrf2 antioxidant defences. Human data derive mainly from hesperidin supplementation studies.

• cherryScientific

  Tart cherry's anthocyanins modulate immune-inflammatory signaling by inhibiting COX-1/2 and NF-κB, reducing TNF-α, IL-1β, and IL-6 in human studies. RCTs demonstrate reduced CRP after exercise, gout flares, and at rest in older adults. These effects reflect immune system modulation rather than simple immunostimulation.

• chia seedScientific

  Chia seeds contain polyphenols, ALA, and zinc that modulate immune-inflammatory signaling. Animal studies show chia reduces pro-inflammatory cytokines (TNF-α, IL-6, NFκB) and stimulates immune cells. A meta-analysis of 4 RCTs confirmed chia significantly reduced CRP in humans.

• chickpea proteinScientific

  Chickpea protein and bioactive compounds modulate immune function by reducing pro-inflammatory cytokine expression and supporting gut-associated immune defence. Chickpea protein hydrolysates downregulate inflammatory enzymes COX-2 and iNOS in preclinical models. The prebiotic fibre supports gut barrier integrity, indirectly sustaining mucosal immune function.

• chickweedScientific

  S. media extracts have demonstrated immunomodulatory activity in preclinical studies, reducing pro-inflammatory cytokines (IL-6, COX-2) in human immune cells (PBMCs) and showing potential antiviral activity. Traditional use for immune-relevant conditions is also documented.

• chicoryScientific

  Chicory inulin's prebiotic action enriches Bifidobacterium in the gut, modulates intestinal immune responses, reduces systemic endotoxemia, and suppresses pro-inflammatory cytokines. A systematic review of 50 human RCTs confirmed bifidogenic effects of chicory root fibers starting from 3 g/day, with improved bowel function and immune-related outcomes.

• chinese salvia rootScientific

  Danshen has unique immunomodulatory properties: it suppresses inflammation and allergy (immunosuppressive) while also enhancing immunity against cancer, viruses, and bacteria (immunostimulatory). This dual activity has been demonstrated in animal and cell models. NK cell activation relevant to liver fibrosis protection is one specific mechanism.

• chlorellaScientific

  Multiple human randomized controlled trials demonstrate that Chlorella supplementation enhances innate immune markers, including NK cell activity and pro-inflammatory cytokines (IFN-γ, IL-1β, IL-12). The primary immunoactive constituents are cell-wall polysaccharides, notably β-1,3-glucan, which activate macrophages and modulate cytokine production. Evidence is promising but limited by small sample sizes, and not all trials (e.g., influenza vaccine response) showed significant effects.

• chokeberryScientific

  A human RCT found significant immunomodulatory effects of aronia juice polyphenols. Chokeberry suppresses pro-inflammatory cytokines (TNF-α, IL-6, IL-8) and elevates anti-inflammatory IL-10 in human trials. Antiviral and antimicrobial properties also contribute to immune support. The anti-inflammatory immune effects are mechanistically linked to anthocyanin-mediated NF-κB inhibition.

• chondroitinScientific

  Chondroitin sulfate has well-documented immunomodulatory and anti-inflammatory effects, primarily through suppression of NF-κB activation and downstream pro-inflammatory mediators. CS reduces expression of IL-1β, TNF-α, COX-2, NOS-2, and PLA2 in chondrocytes, synoviocytes, macrophages, and hepatocytes. These effects have been demonstrated both in vitro and corroborated by clinical outcomes in osteoarthritis and psoriasis trials.

• chrysanthemumScientific

  Chrysanthemum polysaccharides and flavonoids show immunomodulatory effects in preclinical studies, including regulation of cytokine production and immune cell activity. A 2025 Frontiers in Pharmacology review identified immunomodulatory effects in 4 studies within a systematic literature analysis.

• chrysinScientific

  Chrysin modulates immune function through NF-κB inhibition, suppression of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-17), and reduction of mast cell infiltration. It demonstrates immunomodulatory effects in arthritic, allergic, and skin inflammatory models, increasing anti-inflammatory IL-4 and IL-10. Evidence is preclinical.

• chymotrypsinScientific

  Chymotrypsin modulates immune function through its anti-inflammatory proteolytic action, degrading pro-inflammatory mediators and modulating cytokine profiles. A PubMed-indexed animal study showed dose-dependent chymotrypsin treatment decreased pro-inflammatory IL-17 and increased anti-inflammatory IL-4 and FoxP3 in an autoimmune CNS model. It is also described as enhancing immune function by degrading plasma proteins and inflammatory mediators.

• cinnamonScientific

  Cinnamon has documented immunomodulatory activity: its compounds modulate NF-κB-driven cytokine expression, demonstrate broad antimicrobial and antifungal activity, and have antiviral properties. Clinical data show reductions in CRP, TNF-α, and IL-6 in multiple populations. Traditional use as an antimicrobial and immune-supporting spice is documented across major medical traditions.

• citrus pectinScientific

  Citrus pectin modulates immune function through galectin-3 inhibition (affecting inflammatory cascades and immune cell signaling), TLR2-pathway modulation, and prebiotic-driven gut immune normalization. Human studies show normalization of inflammatory cytokine profiles (IL-10/IL-12 ratio) and reduction in TNF-alpha with low-methoxy citrus pectin supplementation.

• citrus sinensisScientific

  Vitamin C from C. sinensis is essential for immune function, with well-documented roles in leukocyte activity, phagocytosis, NK cell activity, T-lymphocyte function, and antibody production. Immune cells accumulate vitamin C at 50–100× plasma concentrations. C. sinensis flavanones also exhibit anti-inflammatory and antiviral properties.

• CLA (conjugated linoleic acid)Scientific

  CLA has documented immunomodulatory properties. Clinical evidence includes modulation of cytokine production, enhancement of antibody responses after vaccination, reduction of allergic responses, and attenuation of inflammatory cell activity in RA patients. CLA interacts with PPARγ to modulate immune cell function.

• cleaversScientific

  Multiple in vitro and animal studies have evaluated G. aparine for immunomodulatory activity, demonstrating lymphocyte stimulation, splenocyte proliferation, and NK cell enhancement. Preclinical evidence is the strongest scientific evidence base for any of cleavers' properties.

• clerodendrum indicumScientific

  C. indicum leaf extracts demonstrate significant antimicrobial activity against multiple bacterial strains in vitro, supporting immune defense relevance. The plant's anti-inflammatory properties (carrageenan model, in vivo) and antioxidant capacity (DPPH) also contribute to immunomodulatory activity documented at the preclinical level across genus-level studies.

• cloveScientific

  Clove and eugenol exert documented immunomodulatory effects, inhibiting NF-κB, suppressing pro-inflammatory cytokine production, and exhibiting broad-spectrum antimicrobial and antiviral activity. These properties have been confirmed in multiple in vitro and animal studies.

• cocoaScientific

  Cocoa polyphenols exert anti-inflammatory effects on immune function, reducing pro-inflammatory cytokines (TNF-α, IL-6, hs-CRP) in clinical trials. Cocoa's modulation of gut microbiota—which profoundly influences immune regulation—and its antioxidant properties further support immune system homeostasis.

• coconutScientific

  Lauric acid from coconut oil and its derivative monolaurin demonstrate antimicrobial, antiviral, and antifungal activities that support immune defense against pathogens. VCO supplementation in an animal model of cyclophosphamide-induced immunosuppression showed protective immune effects. Direct human RCT data on immune endpoints remain limited.

• coconut milkScientific

  Lauric acid in coconut milk converts to monolaurin in vivo, which disrupts lipid membranes of enveloped viruses and pathogenic bacteria. VCO polyphenols modulate TLR/NF-κB inflammatory signaling in human immune cells. Traditional use of coconut as an immunomodulatory food is documented across tropical cultures and is supported by modern mechanistic research.

• coconut oilScientific

  Lauric acid in coconut oil is converted to monolaurin in the body, which has demonstrated broad-spectrum antimicrobial and antiviral activity against gram-positive bacteria, Candida, and enveloped viruses including herpes simplex, RSV, and influenza. Human evidence is limited to small clinical trials; most robust immune data derive from in vitro and animal studies.

• cod liver oilScientific

  Vitamins A and D from cod liver oil are critical immunoregulatory nutrients. Vitamin A maintains mucosal immunity and supports lymphocyte differentiation; vitamin D activates innate immune pathways including cathelicidin. EPA and DHA modulate inflammatory cytokine production. CLO use in infancy is associated with reduced autoimmune risk.

• coixScientific

  Coix seed polysaccharides and coixol demonstrate immunomodulatory activity, enhancing macrophage function, modulating cytokine production, and suppressing aberrant immune activation. In Japan, its immune-modulating activity is recognized as the basis for its approved wart treatment.

• collardScientific

  Collard greens are rich in vitamins A and C — key vitamins for innate and adaptive immunity. Vitamin A is critical for T-cell production and mucosal barrier integrity; vitamin C supports white blood cell function and antibody synthesis. One cup provides 27% DV vitamin C and significant provitamin A carotenoids.

• colostrumScientific

  Bovine colostrum contains immunoglobulins (primarily IgG), lactoferrin, cytokines, and growth factors that support immune function. Multiple randomized controlled trials and systematic reviews demonstrate a significant reduction in upper respiratory tract infection (URTI) risk with supplementation. Evidence is strongest in athletes and individuals with elevated pathogen exposure, though the precise immunological mechanisms remain incompletely characterized.

• coltsfootScientific

  Coltsfoot is high in polysaccharides documented to be immune-stimulating in vitro and in vivo. Extracts of the whole plant have been shown to increase immune resistance in preclinical research. Polysaccharides exert anti-inflammatory and immunomodulatory effects through macrophage and lymphocyte activation.

• commiphoraScientific

  Commiphora myrrh resin stimulates macrophage activation and maturation, modulates WBC counts, and inhibits key pro-inflammatory cytokines (IL-6, TNF-α). These immunomodulatory effects are documented in animal studies and in vitro human cell models.

• copperScientific

  Copper is critical for both innate and adaptive immune function. Deficiency decreases humoral and cell-mediated immunity, impairs macrophage superoxide production, and reduces lymphocyte proliferation. Copper metabolism shifts during inflammation and infection. Human and animal evidence firmly establishes copper as an immune-regulatory mineral.

• coptis chinensisScientific

  Coptis chinensis modulates immune function through berberine's effects on macrophage activation, NF-κB inhibition, cytokine regulation, and antimicrobial defense. Animal studies show immunomodulatory effects in fungal and bacterial infection models, and the herb is classified as an immune-modulating antimicrobial in TCM.

• CoQ10 (coenzyme Q10)Scientific

  CoQ10 modulates immune function by regulating lysosomal and peroxisomal activity during immune responses, suppressing NF-κB-driven pro-inflammatory cytokines (IL-1, IL-6, TNF-α), and preventing lipid peroxidation in immune cells. Clinical evidence includes CKD trials showing CoQ10 reduced plasma CRP and IL-13, and reduced inflammatory gene expression via NF-κB pathway suppression.

• cordycepsScientific

  Cordyceps (primarily C. sinensis and C. militaris) demonstrates bidirectional immunomodulatory activity supported by in vitro, animal, and human clinical data. Key bioactive constituents — polysaccharides and cordycepin — activate macrophages, NK cells, lymphocytes, and dendritic cells while also suppressing overactivated immune responses. Multiple randomized, double-blind, placebo-controlled trials in healthy adults confirm measurable enhancement of NK cell cytotoxic activity. Evidence quality is moderate; most human trials are small and many originate from China, warranting cautious interpretation.

• cranberryScientific

  A limited but credible body of evidence suggests cranberry polyphenols can modulate systemic immune function, partly via gut microbiome interactions. A randomized double-blind trial showed increased proliferation of γδ-T cells — immune sentinels of the gastrointestinal and reproductive tracts — after 10 weeks of cranberry beverage consumption. Evidence remains preliminary but is human-based.

• cryptoxanthinScientific

  BCX, via its provitamin A conversion to retinol, supports immune epithelial barrier integrity, lymphocyte differentiation, and antibody production. It also directly modulates macrophage polarization from pro-inflammatory M1 to anti-inflammatory M2 subtypes, and was shown to evoke redox and immune changes in macrophages in vitro.

• cuminScientific

  Cumin's antioxidant and antimicrobial properties support immune defense. Its flavonoids and polyphenols reduce oxidative stress that impairs immune function. In vitro studies confirm inhibition of E. coli, Salmonella, and Listeria. Clinical inflammatory marker reductions (TNF-α, hsCRP) have been demonstrated in RCTs.

• curcuminScientific

  Curcumin, the principal polyphenol of turmeric (Curcuma longa), has well-documented immunomodulatory effects supported by both preclinical research and human clinical trials. It modulates key inflammatory signaling pathways—particularly NF-κB, AP-1, and MAPKs—and influences multiple immune cell types including T cells, macrophages, dendritic cells, B cells, and NK cells. Clinical trials in immune-mediated conditions such as rheumatoid arthritis, ulcerative colitis, and obesity have demonstrated reductions in pro-inflammatory cytokines and inflammatory markers. A major limitation across studies is curcumin's inherently poor oral bioavailability, which has driven development of enhanced formulations.

• currantScientific

  Blackcurrant seed oil GLA modulates immune response in human trials, augmenting T-cell and NK-cell function in elderly subjects. Blackcurrant anthocyanins have immunostimulatory properties demonstrated in clinical research. Seed oil has also been studied for shifting Th1/Th2 cytokine balance.

• d-alpha tocopherolScientific

  Alpha-tocopherol enhances immune function by increasing T-cell proliferation, improving T-helper cell responses, enhancing antibody production, and reducing prostaglandin E2-mediated immune suppression. Controlled human trials demonstrate significant improvements in immune markers and vaccine responses in elderly subjects.

• dandelionScientific

  Dandelion polysaccharides possess documented immunomodulatory activity in preclinical models, including activation of macrophages and modulation of cytokine production. TCM traditionally uses dandelion to enhance immune response to respiratory infections. Sesquiterpene lactones also exert immunomodulatory effects.

• delta-tocopherolScientific

  Delta-tocopherol, as part of the vitamin E family, modulates immune function through suppression of NF-κB, reduction of pro-inflammatory cytokines (IL-6, TNF-α), inhibition of COX-2, and reduction of oxidative stress in immune cells. Mixed tocopherols containing delta-tocopherol demonstrate better anti-inflammatory and immunomodulatory actions than α-tocopherol alone. These effects are documented in stimulated human endothelial and immune cell models.

• DHA (docosahexaenoic acid)Scientific

  DHA modulates immune function through multiple pathways: it is enzymatically converted to specialized pro-resolving mediators (resolvins, protectins, maresins) that resolve acute inflammation, suppresses pro-inflammatory cytokine production, and preserves immune cell concentrations and phagocytic function. Clinical evidence from human studies demonstrates reductions in IL-6, CRP, and preservation of immune cell function with DHA+EPA supplementation.

• DHEA (dehydroepiandrosterone)Scientific

  DHEA has documented immunomodulatory properties including inhibition of proinflammatory cytokine production, modulation of the Th1/Th2 balance, and anti-glucocorticoid effects on immune cells. Low DHEA levels are associated with immune dysfunction and several autoimmune diseases. DHEA has been shown to increase IL-2 levels in animal models and to reduce IL-6 in human studies.

• diamine oxidaseScientific

  DAO is a key regulator of histamine homeostasis, and histamine is a fundamental immune mediator acting on H1–H4 receptors distributed across immune cells including mast cells, basophils, dendritic cells, and T lymphocytes. DAO deficiency permits excess histamine to dysregulate immune responses, producing pseudo-allergic inflammatory states.

• DIM (diindolylmethane)Scientific

  DIM has demonstrated immunomodulatory effects in multiple preclinical models, including suppression of activated T cells, reduction of pro-inflammatory cytokines, and protection against autoimmune pathology. A PMC-indexed study showed DIM reduced EAE severity in mice via microRNA-mediated T cell apoptosis. DIM also enhances immune responses against HPV-associated cervical dysplasia in animal models.

• dioscoreaScientific

  Dioscorea polysaccharides and extracts have demonstrated immunomodulatory effects in animal and cell studies, enhancing antioxidant enzyme activity, modulating macrophage function, and reducing inflammatory cytokines. The 2024 systematic review identified immunomodulation as a primary mechanism of gastrointestinal benefit.

• docosahexaenoic acidScientific

  DHA modulates immune function by regulating inflammatory gene expression, reducing pro-inflammatory cytokine synthesis (TNF-α, IL-1β), and generating specialized pro-resolving mediators (resolvins, protectins) that actively terminate inflammation. DHA shifts eicosanoid balance toward anti-inflammatory profiles and supports immune resolution without immune suppression.

• dodderScientific

  Cuscuta chinensis polysaccharides have demonstrated immunomodulatory and immunostimulant effects in multiple animal studies. Effects include increased thymus and spleen weight, enhanced macrophage phagocytosis, stimulated splenocyte proliferation, and elevated interleukin production. An acidic polysaccharide from C. chinensis seeds was structurally characterized specifically for its immunostimulating properties.

• dog roseScientific

  Rosa canina is one of the richest botanical sources of vitamin C, a key immune cofactor that promotes white blood cell production and antibody synthesis. Rosehip also exhibits immunomodulatory effects, having been shown to stimulate white blood cell production and modulate autoimmune inflammatory responses. These properties are supported by mechanistic and some clinical data.

• dogwoodScientific

  Cornus officinalis has preclinical immunomodulatory activity documented across multiple PMC reviews. Polysaccharide fractions are particularly active. Preclinical studies show regulation of T and B lymphocytes and macrophage activity in bone and systemic immune contexts. No human immunological trials exist.

• dong quaiScientific

  A. sinensis polysaccharides have been extensively studied for immunomodulatory effects, including stimulation of phagocytic activity, IL-2 production, NK cell activity, and macrophage polarization. These effects are supported by multiple in vitro and animal studies, with some human data in cancer populations. The MDPI 2026 review specifically focuses on Dong Quai's immunomodulatory mechanisms.

• DPA (docosapentaenoic acid)Scientific

  DPA generates a distinct series of specialized pro-resolving mediators (RvDPA, MaR1n-3 DPA, protectins) that direct immune cell behavior to resolve—rather than suppress—inflammatory responses. These mediators increase macrophage phagocytic activity, promote neutrophil apoptosis, and enhance monocyte differentiation. DPA's immune-modulatory properties are documented in human leukocyte preparations.

• DPPIV (peptidase)Scientific

  DPPIV is identical to CD26, a well-characterized T-cell surface antigen that plays a documented role in T-cell co-stimulation, chemokine processing, and immune cell trafficking. Multiple peer-reviewed studies have established that CD26/DPPIV modulates T-cell activation and co-stimulation and cleaves immunoregulatory chemokines including RANTES and SDF-1α, altering their chemotactic and signaling activity. This immune function is distinct from its digestive role and is supported by substantial basic and translational science.

• dulse leafScientific

  A phenolic dulse extract (DULEXT) significantly modulated primary human neutrophil activation by down-regulating TLR4, reducing IL-1β, IL-6, TNF-α, IL-8, ROS, nitric oxide, and myeloperoxidase in LPS-stimulated cells. Dulse polysaccharides also enhanced beneficial Lactobacillus populations in a mouse model, with downstream immune-modulatory implications. These findings represent in vitro and animal-level immune science.

• echinaceaScientific

  Echinacea has a substantial body of clinical and preclinical evidence supporting its role as an immunomodulator, primarily studied for upper respiratory tract infections (URTIs). Multiple controlled clinical trials and meta-analyses indicate modest but measurable benefits—reducing cold incidence and shortening duration—though evidence quality is variable and results are inconsistent across preparations. Key bioactive constituents (alkamides, polysaccharides, caffeic acid derivatives) are documented to activate macrophages, NK cells, and cytokine pathways. Overall, the scientific basis is real but not yet conclusive, with preparation heterogeneity being a major confounding factor.

• echinacea purpureaScientific

  Immunomodulation is the best-evidenced pharmacological property of E. purpurea, supported by numerous RCTs, systematic reviews, and official regulatory recognition. The plant modulates both innate and adaptive immunity through multiple phytochemical classes. The EMA HMPC, WHO, German Commission E, and NCCIH all recognize this relationship.

• EGCG (epigallocatechin gallate)Scientific

  EGCG, the predominant catechin in green tea, exerts well-documented immunomodulatory effects on both innate and adaptive immune cells, principally by suppressing pro-inflammatory signaling via NF-κB and STAT1/3 inhibition. It modulates T cell proliferation and differentiation, upregulates regulatory T cells, and demonstrates antiviral activity against multiple human pathogens. Evidence spans in vitro studies on human primary immune cells, animal models, and some human clinical data on inflammatory cytokine reduction.

• eggScientific

  Egg components demonstrate immunomodulatory activity in clinical and preclinical studies. A clinical RCT found one egg/day significantly reduced pro-inflammatory cytokines (TNF-α, IL-6) in type 2 diabetic patients. Egg-derived bioactive peptides and compounds also possess documented anti-inflammatory and antioxidant properties relevant to immune regulation.

• eicosapentaenoic acidScientific

  EPA modulates innate and adaptive immune responses by reducing pro-inflammatory cytokine production, shifting macrophage polarization toward anti-inflammatory phenotypes, and generating specialized pro-resolving mediators (E-series resolvins). Clinical evidence spans RA, IBD, and sepsis, with EPA-enriched enteral nutrition recommended for mechanically ventilated patients with severe lung injury.

• elderberryScientific

  Elderberry (Sambucus nigra) has documented clinical evidence supporting immune-related activity, particularly in reducing the duration and severity of upper respiratory viral infections. A 2019 meta-analysis of randomized controlled trials found supplementation substantially reduced upper respiratory symptoms compared to placebo. The European Medicines Agency (EMA) has monographed elderberry as a traditional herbal medicinal product for respiratory infection prevention. Overall evidence is promising but rated moderate-to-low certainty due to small trial sizes and methodological limitations.

• elecampaneScientific

  Elecampane and alantolactone have been shown in multiple in vitro studies to modulate immune function, including suppression of neutrophil pro-inflammatory mediators, inhibition of NF-κB and toll-like receptor signaling, and immunomodulatory effects comparable to budesonide in one assay. The British Herbal Pharmacopoeia classifies it as diaphoretic and immunostimulant in traditional systems.

• eleutheroScientific

  Eleuthero (Eleutherococcus senticosus) has both a long traditional history and some clinical/in vitro evidence of immunomodulatory activity, primarily attributed to its eleutherosides B and E. A placebo-controlled human trial showed increased T-lymphocyte subsets in healthy volunteers, and in vitro work demonstrated cytokine induction. However, robust clinical evidence is limited by small sample sizes, methodological heterogeneity, and poor standardization of preparations. Overall, the immune-supporting claims are biologically plausible but not yet conclusively proven in humans.

• enicostemma littoraleScientific

  E. littorale methanolic extract demonstrated immunomodulatory activity in Dalton's ascitic lymphoma (DAL) mice, enhancing mean survival time and peritoneal cell counts. Anti-inflammatory cytokine modulation (TNF-α suppression, IL-10 upregulation) supports immune-regulatory activity. Traditional medicine also classifies the plant as an immunomodulator.

• EPA (eicosapentaenoic acid)Scientific

  EPA modulates immune function by incorporating into immune cell membranes and shifting eicosanoid production from pro-inflammatory arachidonic acid derivatives toward anti-inflammatory resolvins and protectins. Clinical evidence documents EPA's suppression of pro-inflammatory cytokines (TNF-α, IL-6) and its ability to reduce markers of systemic inflammation such as CRP and fecal calprotectin.

• eucalyptusScientific

  Eucalyptus oil and 1,8-cineole modulate immune function through stimulation of phagocytic activity in macrophages and monocytes at lower doses, suppression of pro-inflammatory cytokine cascades (TNF-α, IL-1β, IL-6), and immunoregulatory effects documented in preclinical and some clinical settings. These dual immunostimulatory and anti-inflammatory effects make it of clinical interest in infectious and inflammatory disease.

• eucommiaScientific

  E. ulmoides extracts significantly inhibit pro-inflammatory cytokines in human immune cells (neutrophils, macrophages, THP-1). In animal models, immunoregulatory and immunomodulatory activities including NLRP3 suppression, NF-κB inhibition, and anti-arthritic effects are documented. Immunoregulation is listed as an established property in comprehensive pharmacological reviews.

• european elderScientific

  Elderberry is one of the most clinically studied botanicals for immune modulation. It stimulates cytokine production (IL-6, IL-8, IL-12), modulates lymphocyte proliferation, and has antiviral properties confirmed in human ex vivo studies and RCTs. The EMA, German Commission E, and WHO all recognize elderflower preparations for immune-supportive use against cold and flu.

• ferula assafoetidaScientific

  Asafoetida modulates immune function by suppressing pro-inflammatory cytokines (TNF-α, IL-6, IL-1β), reducing VCAM-1/ICAM-1-mediated leukocyte adhesion in endothelial cells, and exhibiting broad antimicrobial and antifungal activity. These effects are supported by in vitro and preclinical studies.

• ferulic acidScientific

  Ferulic acid modulates the immune system by suppressing NF-κB and NLRP3 inflammasome activation, reducing pro-inflammatory cytokines (IL-1β, IL-6, TNF-α), and inhibiting COX-2 and iNOS. The 33% reduction in hs-CRP in the human RCT reflects systemic immunomodulatory action. FA also inhibits microglial activation in neuroinflammation models.

• feverfewScientific

  Parthenolide modulates immune signaling by inhibiting NF-κB, reducing TNF-α, IL-2, IL-1β, and IFN-γ production. These immunomodulatory effects have been demonstrated in multiple in vitro studies using human immune cells. The effects suggest a capacity to dampen excessive immune activation without complete suppression.

• fisetinScientific

  Fisetin modulates innate and adaptive immunity through NF-κB, TLR4, β-catenin, and NLRP3 inflammasome pathway suppression, reducing macrophage/neutrophil overactivation and increasing IL-10. It also reduces the burden of senescent immune cells (T, NK cells) identified in the landmark EBioMedicine 2018 paper.

• fish oilScientific

  Fish oil EPA and DHA exert broad immunomodulatory effects, shifting the balance from pro-inflammatory to pro-resolving immune activity. They reduce production of TNF-α, IL-1β, IL-6, and leukotriene B4 while upregulating resolvins, protectins, and maresins that promote immune resolution. Clinical evidence shows fish oil reduces CRP and inflammatory cytokines in multiple disease populations.

• flavin mononucleotideScientific

  Riboflavin (via FMN/FAD) contributes to immune function; deficiency impairs immune responses and FMN modulates microglial and macrophage inflammatory signaling. StatPearls and other authoritative sources document immune function among the systems dependent on adequate FMN/FAD status.

• flaxseedScientific

  Flaxseed's ALA omega-3 and lignans modulate immune function by reducing pro-inflammatory cytokines (TNF-α, IL-6, hs-CRP). A 2019 meta-analysis of 32 clinical trials found significant reductions in these inflammatory markers. A pilot human study in cystic fibrosis showed Nrf2 antioxidant enzyme upregulation.

• flowering quinceScientific

  C. speciosa extracts exhibit immunoregulatory properties, including modulation of macrophage activity and cytokine production. Glucosides show anti-inflammatory and immunoregulatory actions, and animal tumor studies demonstrate immune-enhancing effects. These findings are preclinical.

• forskohlii rootScientific

  Forskolin inhibits mast cell degranulation and release of histamine, leukotrienes, and platelet-activating factor (PAF) via cAMP elevation, reducing allergic and inflammatory immune responses. These effects have been demonstrated in preclinical studies and have mechanistic relevance to asthma and allergic clinical trials.

• forsythiaScientific

  Forsythia is widely described in TCM as a fundamental herb for immune support, particularly for infectious and febrile diseases. Preclinical research confirms its antiviral, antibacterial, and immunomodulatory properties through NF-κB, TLR4, and RIG-I signaling pathways. Combination formulas containing Forsythia have been used clinically in China for influenza and COVID-19.

• FOS (fructooligosaccharides)Scientific

  FOS supplementation increases secretory IgA, enhances immune responses via Bifidobacterium-driven microbiota changes, and modulates peripheral immune cells (monocytes) in human studies. Infant formula trials with FOS/GOS prebiotic blends have reported reductions in upper respiratory and GI infection rates. Most mechanistic immune data originate from animal and in vitro studies.

• fritillaryScientific

  Fritillary alkaloids modulate immune responses via inhibition of NF-κB, suppression of Th2 cytokines and IgE, reduction of eosinophilic infiltration, and STAT pathway-mediated immunoregulation. It is listed as an immunity promoter in traditional sources and the immune modulating pharmacology is well documented preclinically.

• fu lingScientific

  Poria cocos polysaccharides and triterpenoids modulate innate and adaptive immunity, stimulating macrophage, NK cell, and T-cell activity while also suppressing excessive Th2 responses. Immunomodulatory effects are documented via macrophage NF-κB pathway activation, IFN-γ promotion, and Treg induction. Some polysaccharide formulations are used clinically as adjunctive immune agents in Asia.

• fucoidanScientific

  Fucoidan, a sulfated polysaccharide from brown seaweed, has documented immunomodulatory effects supported by in vitro, animal, and human clinical evidence. It activates multiple branches of the immune system, including NK cells, dendritic cells, macrophages, and T cells, while also reducing pro-inflammatory cytokines. Human trials include a randomized, double-blind, placebo-controlled study in elderly subjects showing enhanced antibody responses to influenza vaccination at 300 mg/day of Undaria pinnatifida fucoidan. Evidence is promising but constrained by small sample sizes and heterogeneity across fucoidan sources.

• fulvic acidScientific

  FvA is the most-studied humic substance for immune modulation. It exhibits both immunostimulant and immunosuppressive effects depending on dose and context. A pilot human study showed topical FvA reduced allergen-driven immune reactions. In vitro studies document TNF-α, COX-2, and PGE2 modulation in human immune cells.

• fungal proteaseScientific

  Systemic proteolytic enzymes including microbial/fungal proteases are proposed to modulate immune function by degrading circulating immune complexes, reducing pro-inflammatory cytokines, and clearing inflammatory debris. Clinical evidence shows reductions in CRP with fungal protease supplementation, and mechanistic research supports protease involvement in immune complex regulation.

• gamma tocopherolScientific

  Gamma-tocopherol modulates innate immune responses by suppressing NF-κB activation, reducing pro-inflammatory cytokine production, limiting neutrophil infiltration, and attenuating IgE-mediated basophil responses. Human Phase I studies show γT supplementation decreases ex vivo monocyte cytokine responses and NF-κB/JNK signaling.

• ganodermaScientific

  Ganoderma lucidum is one of the most studied medicinal mushrooms for immunomodulation, with documented activation of NK cells, dendritic cells, macrophages, T-cells, and B-cells. Clinical studies show improved immune cell counts in cancer patients; this is the most evidence-rich area for Ganoderma.

• garbanzo beanScientific

  Garbanzo beans support immune function via multiple nutrients: selenium supports glutathione peroxidase and antioxidant enzyme activity critical for immune cell function; zinc (present in chickpeas) is required for lymphocyte proliferation; polyphenols modulate immune cell signaling; and prebiotic fiber fosters gut microbiome composition that supports mucosal immune defense. Cell-model studies confirm chickpea digests upregulate anti-inflammatory cytokines (IL-10) in macrophages.

• gardeniaScientific

  Gardenia jasminoides and its constituents regulate both innate and adaptive immune responses. Genipin inhibits T cell activation via ORAI1 calcium channel modulation, suppresses NF-κB and NLRP3 inflammasome in macrophages, and reduces allergic inflammation. Geniposide has immunosuppressive activity documented in network pharmacology and preclinical studies.

• gardenia jasminoidesScientific

  Gardenia jasminoides and genipin/geniposide modulate immune function through suppression of T cell activation (ORAI1 channel inhibition on CD4+ T cells), reduction of macrophage-mediated pro-inflammatory cytokine production, suppression of IgE and mast cell degranulation, and NF-κB pathway inhibition. Both immunosuppressive and immune-regulatory activities are documented across in vitro and animal models.

• garlicScientific

  Garlic (Allium sativum) has human clinical evidence supporting immune modulation, primarily through its organosulfur compounds (OSCs) such as allicin. Multiple RCTs and meta-analyses show garlic supplementation reduces circulating inflammatory markers (CRP, TNF-α) and enhances innate immune cell activity (NK and γδ-T cells). Evidence is most consistent for aged garlic extract (AGE), though overall study quality remains a limiting factor.

• garlic bulbScientific

  Garlic's organosulfur compounds enhance innate immunity (macrophages, NK cells) and adaptive immunity (T and B cells). Clinical evidence includes a double-blind RCT demonstrating AGE enhanced NK and γδ-T cell function and reduced cold/flu severity. Garlic also demonstrates broad-spectrum antimicrobial, antiviral, and antifungal activity.

• gastrodiaScientific

  GE polysaccharides exhibit immunomodulatory effects including regulation of microglial activation and cytokine release. GE modulates innate immune pathways (NF-κB, MAPK) and has anti-tumor and antiviral effects documented in preclinical research.

• genisteinScientific

  Genistein modulates immune function through inhibition of NF-κB, suppression of proinflammatory cytokine production (TNF-α, IL-6, IL-1β), modulation of macrophage polarization, and effects on T-cell function. Animal studies show it reverses signs of autoimmune encephalomyelitis by downregulating proinflammatory cytokines. Clinical data show reductions in inflammatory markers in human trials.

• gentian rootScientific

  Gentian root extract has been shown in a human pharmacological study (cited in the ESCOP monograph) to elevate secretory immunoglobulin A (sIgA) levels, a key mucosal immune effector. G. scabra polysaccharides have demonstrated immunological activity in cell studies. Gentian is a component of the clinically studied sinusitis formula Sinupret, suggesting immune-mucosal activity. Most immune-related evidence remains preclinical.

• gentiana macrophyllaScientific

  Gentiana macrophylla demonstrates immunomodulatory activity in preclinical research, influencing inflammatory cytokine networks and modulating immune responses in autoimmune models. The 2024 comprehensive review identifies 'immunomodulatory' activity as one of GMR's primary pharmacological effects. Gentiopicroside modulates NLRP3 inflammasome and NF-κB signaling pathways central to innate immune regulation.

• geraniumScientific

  Pelargonium (especially P. sidoides) activates non-specific immune functions including macrophage activation, NK cell enhancement, and secretory IgA production. P. graveolens shows in vitro immunostimulant and antioxidant effects. These actions are well documented across laboratory and clinical studies.

• gingerScientific

  Ginger exhibits well-documented immunomodulatory, anti-inflammatory, and antimicrobial properties. It inhibits NF-κB signaling, suppresses pro-inflammatory cytokines (TNF-α, IL-1β, IL-6), and modulates COX and LOX pathways. These immune-relevant mechanisms have been confirmed in preclinical studies and are implicated in human clinical trials for inflammatory conditions.

• ginsengScientific

  Panax ginseng has well-documented immunomodulatory effects supported by both mechanistic research and human clinical trials. Its primary bioactive compounds, ginsenosides, modulate key immune cells including macrophages, NK cells, dendritic cells, T cells, and B cells. Multiple randomized controlled trials demonstrate reduced incidence and severity of respiratory infections and enhanced vaccine-induced antibody responses. Evidence quality is meaningful but heterogeneous, with many trials small in scale.

• GLA (gamma linolenic acid)Scientific

  GLA and its metabolite DGLA modulate immune cell function by shifting eicosanoid production away from pro-inflammatory arachidonic acid-derived mediators and toward anti-inflammatory PGE1 and 15-OH-DGLA. Clinical evidence shows GLA supplementation influences cytokine levels, T-cell function, and immune response in elderly subjects.

• glehnia littoralisScientific

  Immunoregulatory activity is among the most consistently confirmed pharmacological properties of G. littoralis across multiple published studies and systematic reviews. Polysaccharides modulate lymphocyte proliferation and macrophage function; extracts suppress pro-inflammatory immune mediators via NF-κB/MAPK pathways.

• glehnia rootScientific

  Preclinical studies have demonstrated immunoregulatory, immunomodulatory, and T-cell-stimulating effects of G. littoralis extracts and polysaccharide fractions. The 2019 systematic review identifies strong evidence for immunoregulatory potential. No human data exist.

• glucomannanScientific

  Glucomannan modulates immune function through its prebiotic action on gut microbiota, which regulates immune cell signaling, and through direct immunomodulatory properties. Animal and in vitro studies show it enhances immunocompetence and suppresses allergic/inflammatory responses; human evidence is limited but supported by its gut microbiota-immune axis effects.

• glutamic acidScientific

  Glutamic acid contributes to immune function primarily as a precursor to glutathione, the principal intracellular antioxidant used by immune cells to resist oxidative damage during immune activation. Glutamate also functions as an immune mediator in glial cells and peripheral immune tissue. Dietary glutamic acid has been shown to modulate immune responses, cytokine profiles, and gut-associated immune cell activity.

• glycineScientific

  Glycine is characterized as a novel anti-inflammatory, immunomodulatory, and cytoprotective agent (Zhong et al., 2003). It activates glycine-gated chloride channels on macrophages, Kupffer cells, and neutrophils, blunting superoxide and TNF-α production. Human clinical trials show glycine modulates cytokine profiles in T2D patients.

• goji berryScientific

  LBP is a well-characterized immunomodulator that interacts with toll-like receptors, upregulates IL-2 and IFN-γ, and enhances innate and adaptive immune responses. A 3-month human study in 150 older adults showed goji supplements significantly boosted immune response to a flu vaccine. Preclinical studies consistently demonstrate LBP's immunomodulatory properties.

• goldensealScientific

  Goldenseal has demonstrated immunomodulatory effects in animal research, with a published study showing increased production of antigen-specific immunoglobulins following goldenseal administration. Berberine also stimulates immune function, and this relationship has some scientific support beyond pure tradition.

• gooseberryScientific

  Amla is one of the most widely used Ayurvedic immune-supporting herbs, and modern research confirms its immunomodulatory effects through multiple pathways. Animal studies show enhanced immune markers, and a COVID-19 add-on RCT has been published. Its exceptionally high vitamin C content supports innate immunity.

• gotu kolaScientific

  Gotu Kola modulates immune function through suppression of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IgE), upregulation of anti-inflammatory mediators (IL-10, TGF-β), and enhancement of macrophage IL-1β secretion at picomolar concentrations. Its triterpenes shift immune responses from pro-inflammatory to resolution-phase profiles. Antioxidant upregulation (Nrf2/ARE) also protects immune cells.

• grapeScientific

  Grape polyphenols modulate immune function by reducing pro-inflammatory cytokine secretion from activated leukocytes and reducing markers of systemic inflammation such as CRP. A meta-analysis of 17 RCTs found grape products significantly reduced CRP. Grape polyphenols differentially modulate cytokine secretion from human peripheral blood leukocytes in vitro. GSE improves total antioxidant capacity, protecting immune cells from oxidative damage.

• grape seedScientific

  A meta-analysis of 23 studies found GSE significantly reduced systemic inflammatory markers (malondialdehyde SMD −1.04, oxidized LDL SMD −0.44, hsCRP WMD −0.48 mg/L). GSE suppresses TNF-α, IL-1β, IL-6, and NF-κB signaling. Preclinical evidence shows GSE modulates T-cell balance and Treg differentiation in arthritis and autoimmune models.

• grapefruitScientific

  Grapefruit is a rich source of vitamin C, which supports immune function by stimulating white blood cell production and activity. One whole medium grapefruit provides 100% of the adult daily requirement for vitamin C. Grapefruit also contains zinc and vitamin A, both of which support immune competence.

• green chirettaScientific

  Green chiretta is one of the best-evidenced herbal immunomodulators, with mechanistic, preclinical, and human clinical data supporting its activation of macrophages, NK cells, and lymphocytes, and its modulation of Th1/Th17 responses. Multiple RCTs confirm clinically meaningful immune-mediated effects in URTI, RA, and IBD.

• green teaScientific

  Green tea, via its primary bioactive compound epigallocatechin-3-gallate (EGCG), exerts well-documented immunomodulatory effects on both innate and adaptive immune cells. Human and preclinical evidence demonstrates modulation of T cell activation, differentiation, and cytokine production, as well as enhanced NK cell activity and reduced pro-inflammatory signaling. Most robust mechanistic data comes from animal models, with emerging—but still limited—human clinical trial data supporting these effects.

• green-lipped musselScientific

  GLM contains compounds that modulate immune-mediated inflammatory pathways. Its lipid fraction inhibits COX and 5-LOX enzymes, reducing pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-17) documented in both human OA clinical samples and animal arthritis models. A 2023 PLOS One study in collagen-induced arthritis mice found GLM reduced Th17 cell expansion and inhibited osteoclastogenesis, both immune-mediated processes. GLM also contains zinc and selenium that support innate immune function.

• guggulScientific

  Guggulsterones modulate immune-inflammatory signaling by suppressing NF-κB and downstream cytokines including TNF-α, IL-1, and IL-6, and inhibiting COX-2. These immunomodulatory effects underlie guggul's documented benefits in arthritis, inflammatory bowel disease preclinical models, and cardiovascular inflammation. Human evidence includes CRP reduction in clinical studies.

• gymnema sylvestreScientific

  GS triterpenoid saponins demonstrate immunomodulatory activity in animal models, upregulating IL-2 and IL-4 while suppressing TNF-α, reversing organ atrophy in immunosuppressed rats, and modulating haematopoiesis. In vitro evidence also shows anti-inflammatory effects on macrophages.

• hemicellulaseScientific

  Hemicellulase's glucanase activity can degrade beta-glucans on the Candida cell wall, triggering release of fungal antigens that activate dectin-1 receptors on innate immune cells and stimulate cytokine production (interleukins, TNF-alpha). This mechanism has been documented in published immunology and mycology research. Additionally, hemicellulose-derived oligosaccharides modulate gut microbiota composition, indirectly shaping mucosal immune tone.

• hesperetinScientific

  Hesperetin modulates immune function by inhibiting NF-κB-driven pro-inflammatory cytokine production, suppressing mast cell inflammatory responses, and exhibiting antimicrobial activity. Human RCT evidence shows reduction of TNF-α, a key immune mediator.

• hesperidinScientific

  Hesperidin modulates the immune system by downregulating pro-inflammatory cytokines (TNF-α, IL-1β, IL-4, IL-6, IL-8, IL-12) and upregulating anti-inflammatory IL-10, inhibiting NF-κB, and modulating leukocyte function. A human RCT showed a hesperidin-containing supplement improved immune function in adults and enhanced the oxidative-inflammatory state.

• hibiscusScientific

  Hibiscus sabdariffa is rich in vitamin C and anthocyanins that support immune function by promoting antioxidant defense and modulating inflammatory cytokines. A human clinical study demonstrated reductions in IL-6, IL-1β, and IL-8. Preclinical data support immunomodulatory activity, and traditional use for immune-related and infectious conditions is documented globally.

• HMR (7-hydroxymatairesinol)Scientific

  HMR demonstrated immunomodulatory activity in human cell models: it concentration-dependently suppressed LPS-induced TNF-alpha production in THP-1 monocytes and inhibited oxidative burst in human polymorphonuclear leukocytes (PMNs). These effects are consistent with anti-inflammatory immunomodulation.

• HMR lignanScientific

  HMR exhibits immunomodulatory activity by concentration-dependently reducing LPS-stimulated TNF-α and TNF-α mRNA in THP-1 human monocytes, and reducing ROS and IL-8 production in human polymorphonuclear leukocytes. These effects position HMR as a modulator of both innate monocyte/macrophage and neutrophil arms of the immune response.

• ho woodScientific

  The high linalool content of ho wood essential oil (95–99%) confers broad-spectrum antimicrobial activity against bacteria and fungi, supporting immune defense. Multiple in vitro studies confirm linalool inhibits pathogens including Staphylococcus aureus, Pseudomonas species, Listeria monocytogenes, Klebsiella pneumoniae, Escherichia coli, and Candida albicans. Traditional aromatherapy sources (e.g., Nature's Gift, Aroma-Zone) describe ho wood as a potent immunostimulant. Evidence is primarily preclinical.

• holarrhena antidysentericaScientific

  Immunomodulatory properties of H. antidysenterica are documented in peer-reviewed literature, with the plant listed as immunomodulatory in pharmacological reviews (Atal et al., 1986, cited in multiple studies). Antimicrobial activity of conessine, including efflux pump inhibition, represents a scientifically documented contribution to anti-infective defense.

• hollyScientific

  I. aquifolium ethanolic extract has been shown to inhibit leukotriene B4 biosynthesis in isolated leukocytes in vitro, directly demonstrating immune-modulating activity. The phenolic phytochemicals (chlorogenic acid, rutin) are known to modulate immune signaling pathways.

• honeyScientific

  Honey modulates both innate and adaptive immune responses, stimulating cytokine production, activating macrophages and lymphocytes, and suppressing excessive inflammation via NF-κB and MAPK pathway inhibition. Clinical evidence includes RCTs showing immune benefits in tuberculosis patients, pediatric URTI, and wound infection control. Manuka honey's MGO specifically stimulates MAIT cells.

• honeysuckleScientific

  Honeysuckle possesses well-documented immunomodulatory properties including stimulation of immune cell activity, modulation of Treg/Th17 balance, regulation of cytokine profiles, and antiviral activity against multiple viruses. Polysaccharides are identified as key immune-regulatory components with pleiotropic biological response modifier activity.

• hopsScientific

  Xanthohumol from hops has demonstrated immunomodulatory activity including NF-κB inhibition, suppression of pro-inflammatory cytokines (IL-6, IL-8, TNF-alpha), and antimicrobial properties. It has been characterized as an immune system modulator in peer-reviewed pharmacological reviews. In vitro evidence is robust; human immunological endpoints have been studied indirectly via CRP reduction.

• horehoundScientific

  In vitro studies demonstrate significant antimicrobial activity of horehound extracts and essential oil against bacteria and fungi, and in vitro immunomodulatory activity has been reported. PMC reviews classify immunomodulatory activity among documented properties. Evidence is laboratory-based; human immunological trials have not been conducted.

• horseradishScientific

  Horseradish supports immune function through multiple documented mechanisms: vitamin C content (supporting immune cell activity), antimicrobial isothiocyanates active against a broad range of pathogens, and in vitro immunomodulatory effects including inhibition of TNF-α, COX-2, and NF-κB/MAPK inflammatory pathways. Clinical evidence is primarily via the Angocin combination product for RTI and UTI.

• hyacinth beanScientific

  Pharmacological reviews consistently list immunological activity among the documented effects of L. purpureus. The plant's lectins (FRIL, dolichin), flavonoids, and saponins modulate immune responses. In vitro studies demonstrate both pro-inflammatory lectin activity and anti-inflammatory flavonoid-mediated inhibition of cytokine release.

• hydrangeaScientific

  The halofuginone/Th17 research from the hydrangea family (Dichroa febrifuga) represents the most direct scientific link between hydrangea and immune system modulation. The 2009 Science study demonstrated selective suppression of Th17 cell differentiation in human and mouse T cells, without impairing Th1, Th2, or T-regulatory cells. Additionally, skimmin and coumarin compounds have shown modulation of innate immune markers (IL-1β, IL-6, TNF-α) in animal models.

• hydroxymatairesinolScientific

  HMR modulates human immune cell function directly: in THP-1 human monocytes it concentration-dependently reduces LPS-stimulated TNF-α secretion and mRNA; in human PMNs it reduces ROS and IL-8 production. These results confirm immunomodulatory activity in human cell systems. Evidence is in vitro; no human immune function RCTs have been published.

• hyssopScientific

  Hyssop demonstrates immunomodulatory activity via multiple mechanisms: activation of innate antiviral immunity through endosomal TLR pathways, modulation of inflammatory cytokines, inhibition of IgE-mediated responses, and documented antifungal/antiviral/antibacterial activity in vitro.

• immortelleScientific

  H. italicum modulates immune function through NF-κB inhibition, cytokine suppression (IL-1β, TNF-α, IL-6, IL-8), and anti-HIV and anti-herpes antiviral activity. Arzanol is the principal immunomodulatory compound. A human randomised study confirmed significant reduction in pro-inflammatory immune markers after 4 weeks of oral infusion.

• immunoglobin GScientific

  IgG is the most abundant circulating immunoglobulin and a cornerstone of adaptive immune defense. Oral SBI supports gut-associated immune function by providing luminal IgG that neutralizes antigens, prevents excessive immune activation, and supports mucosal immune reconstitution including CD4+ T cell recovery in immunocompromised patients.

• impatiensScientific

  Impatiens balsamina exhibits immunomodulatory properties — specifically immunosuppressive effects — in addition to antiallergic and anti-histamine activity. These properties have been documented in preclinical pharmacological reviews and are attributed to flavonoids and naphthoquinones.

• indian baelScientific

  Aegle marmelos demonstrates immunomodulatory activity in preclinical studies, modulating IgG/IgM/IgA levels, suppressing proinflammatory cytokines (TNF-alpha, IL-1beta, IL-6), and showing in vitro activity against viruses (rotavirus) and parasites (Giardia). Traditional Ayurvedic immunomodulatory formulations include bael as a component.

• indian frankincenseScientific

  Boswellia serrata demonstrates immunomodulatory activity — reducing pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, IFN-γ) while increasing anti-inflammatory IL-10, and suppressing NF-κB. Formal immunomodulatory activity was documented by Pungle et al. (2003). Clinical evidence in immune-mediated conditions (RA, UC, asthma) confirms in vivo immunological effects.

• indian sarsparillaScientific

  Immunomodulatory properties of H. indicus are documented in preclinical studies showing stimulation of lymphocyte and natural killer cell production. Multiple reviews confirm immunomodulatory activity as a pharmacological property. Ayurvedic texts classify it as immunopotentiating.

• indian tinosporaScientific

  Immunomodulation is the most extensively researched property of T. cordifolia. It activates macrophages, increases leukocyte counts, stimulates colony-stimulating factor production, and modulates both innate and adaptive immune responses. Multiple preclinical studies and clinical data from the allergic rhinitis RCT and COVID-19 trial confirm immune-enhancing activity.

• indigo leavesScientific

  Indigo naturalis exerts immunomodulatory effects documented in both clinical and preclinical studies, including regulation of Th1/Th17 responses, AhR-mediated IL-22 production, and suppression of autoimmune-relevant pathways. RCT-level evidence from psoriasis and UC trials confirms clinically meaningful immune modulation.

• indole-3-carbinolScientific

  I3C acts as an AhR agonist with well-documented immunomodulatory effects, including modulation of macrophage polarization, T- and B-cell maturation, and cytokine expression. Human ex vivo studies in SLE patients show I3C compensates imbalanced pro- and anti-inflammatory cytokine ratios in macrophages. Animal studies demonstrate altered immune cell development relevant to autoimmunity. NF-κB suppression in human leukemia/myeloid cells has been directly demonstrated.

• inula racemosaScientific

  I. racemosa demonstrates preclinical immunomodulatory, antiallergic, antihistamine, and mast cell-stabilizing activities. Its sesquiterpene lactones modulate key immune pathways including NF-κB and MAPK, suppress multiple pro-inflammatory cytokines, and the plant is classified as an immune modulator in Ayurveda.

• inulinScientific

  Inulin and its colonic metabolites modulate intestinal and systemic immune function by promoting beneficial microbiota, enhancing gut barrier integrity, reducing LPS translocation, and stimulating immunomodulatory pathways including IL-22 production. Clinical and mechanistic evidence supports a broad immunomodulatory role via the gut-immune axis.

• iodineScientific

  Thyroid hormones, synthesised using iodine, modulate immune function: lymphocytes bear receptors for thyroid-stimulating hormone and thyroid hormones, and thyroid hormone levels influence thymic and peripheral immune efficiency. Excessive iodine intake can trigger autoimmune thyroid disease through enhanced immunogenicity of iodinated thyroglobulin. Iodine in tissues also acts as a direct antioxidant, influencing local immune responses.

• ironScientific

  Iron is essential for both innate and adaptive immunity. Iron deficiency impairs T lymphocyte proliferation, natural killer cell activation, neutrophil function, and macrophage polarization; it also weakens antibody responses. Conversely, iron overload can impair macrophage-mediated defense. Studies in animals and humans confirm that iron deficiency is associated with impaired delayed-type hypersensitivity responses and reduced mitogen-induced lymphocyte proliferation.

• isoleucineScientific

  Isoleucine plays a documented role in innate immune function by inducing expression of beta-defensins—host defense antimicrobial peptides—via NF-κB activation in epithelial tissues. A 2019 peer-reviewed review (Curr Protein Pept Sci) specifically examined isoleucine's immune roles, finding it improves immune organ function, immune cell activity, and immunoreactive substances. Animal studies show isoleucine supplementation modulates TLR4/NF-κB pathway inflammation.

• isomalto-oligosaccharideScientific

  IMO modulates immune function through its prebiotic promotion of Lactobacillus and Bifidobacterium, which enhance Th-1 immune responses and mucosal IgA secretion. Prebiotic microbiome restoration reduces LPS translocation and systemic immune activation. Animal and some indirect human evidence support this relationship.

• jiaogulanScientific

  Jiaogulan has documented immune-potentiating effects, including increased lymphocyte, phagocyte, and NK cell activity, and elevated serum IgG, based on laboratory and animal studies. It is described as helping the body resist immune suppression under stress conditions.

• jujubeScientific

  Jujube polysaccharides exert immunomodulatory effects including bi-directional immune regulation, anti-allergic activity, antihistaminic effects, and suppression of anaphylactic responses in animal models. Polysaccharides also modulate cytokine production (TNF-α, IL-6, IL-1β) and have been identified as promising immunomodulatory agents in multiple reviews.

• kaleScientific

  Kale provides vitamins A (beta-carotene), C, and E—all critical immune system micronutrients. Sulforaphane activates Nrf2, which modulates immune signaling and reduces chronic inflammatory immune activation. I3C from kale has demonstrated immune-modulatory effects in preclinical studies.

• kelpScientific

  Kelp's fucoidan stimulates dendritic cells, NK cells, and T cells, and delays neutrophil apoptosis in human cell assays. A human RCT found fucoidan consumption one month before influenza vaccination boosted post-vaccination antibody production in immunocompromised elderly. Kelp extracts also stimulate B lymphocytes and macrophages in documented clinical studies.

• knotweedScientific

  A 2015 animal study found Japanese knotweed extract stimulated immune cells and enhanced phagocytosis. In a human trial, 40 mg resveratrol from PC suppressed ROS in immune cells over 6 weeks. Knotweed shows potent in vitro antimicrobial activity against Borrelia, Bartonella, and other pathogens. Resveratrol modulates cytokine production and immune cell signaling.

• krill oilScientific

  Krill oil modulates immune gene expression in human peripheral blood mononuclear cells (PBMCs) in an RCT. Astaxanthin shifts immune response from Th1 to Th2 and suppresses gastric inflammation. In vitro, krill oil dose-dependently inhibits NF-κB-driven IL-1β and TNFα production in human macrophages.

• L-alanyl-L-glutamineScientific

  Glutamine is an essential fuel for lymphocytes, macrophages, and neutrophils, and AG is the preferred clinical delivery form for immune support. AG supplementation maintains immune cell function in catabolic states such as surgery and critical illness. It modulates cytokine production, stimulates immunoglobulin synthesis, and supports mucosal immune responses.

• L-arginineScientific

  L-arginine is integral to immune function: it is a substrate for NO production (which confers antimicrobial properties), and its metabolite ornithine supports polyamine synthesis essential for T-cell proliferation. A 2014 meta-analysis of 11 RCTs found that L-arginine supplementation significantly increased CD4+ T-cell proliferation and reduced infectious complication rates.

• L-cysteineScientific

  L-cysteine drives intracellular glutathione synthesis in immune cells, which is critical for lymphocyte proliferation, T-cell activation, and natural killer cell function. NAC replenishes GSH in peripheral blood lymphocytes and has been shown to modulate immune activity in autoimmune disease. Cysteine availability is rate-limiting for immune cell function under conditions of oxidative stress.

• L-cystineScientific

  L-cystine, as a precursor to cysteine and thus glutathione, supports immune cell function through thiol-dependent redox regulation. Immune cells such as lymphocytes depend on extracellular cysteine/cystine availability for glutathione synthesis and normal proliferation. Glutathione status influences T-cell activation, antioxidant defense, and metabolic detoxification pathways relevant to immune responses.

• L-glutamineScientific

  L-glutamine is an essential fuel for lymphocytes, monocytes, and neutrophils; its depletion impairs cytokine production, lymphocyte proliferation, and phagocytic function. Multiple RCTs in critically ill patients show reduced infectious complications with glutamine supplementation.

• L-glutathioneScientific

  Glutathione is essential for lymphocyte proliferation and immune cell function; intracellular GSH levels regulate T-cell activation and cytokine production. Dietary GSH supplementation has been shown to partially reverse age-associated immune decline in animal models. Normal intracellular GSH exerts critical negative control over NF-κB-mediated pro-inflammatory cytokine elaboration.

• L-glycineScientific

  Glycine modulates immune function through multiple pathways: it activates inhibitory glycine receptors on macrophages and Kupffer cells, reducing inflammatory cytokine release; it supports glutathione synthesis necessary for immune cell antioxidant defense; and it inhibits NF-κB-mediated inflammatory signaling. GlyNAC clinical trials demonstrate correction of inflammation markers in immune-compromised older adults.

• L-histidineScientific

  L-histidine is converted to histamine, a principal mediator of allergic immune responses and mast cell activity. Histidine's anti-inflammatory and antioxidant properties modulate cytokine production, and human RCTs show reductions in TNF-α, IL-6, and CRP with supplementation. Adequate histidine is also required for immune protein synthesis due to its high abundance in immunoglobulins.

• l-isoleucineScientific

  Isoleucine modulates immune function by inducing the expression of host defense peptides (β-defensins), which regulate both innate and adaptive immunity. A 2019 review in Current Protein and Peptide Science (Gu et al.) synthesized evidence that isoleucine improves immune organs, cells, and reactive substances. Animal studies show isoleucine can restore immune defense against pathogens via increased β-defensin expression.

• L-threonineScientific

  L-Threonine is a major structural component of immunoglobulins and is required for normal antibody synthesis. Animal studies consistently show that threonine intake influences serum IgG, IgA, and IgM levels, as well as mucosal secretory IgA. It also stimulates lymphocyte proliferation in vitro. Evidence is primarily from animal models and in vitro studies; human-specific immunological trials are limited.

• L-tryptophanScientific

  L-Tryptophan and its metabolites are pivotal regulators of intestinal immune homeostasis. Tryptophan metabolites (kynurenines, indoles) act as ligands for the aryl hydrocarbon receptor (AhR) on immune cells, modulating tolerogenic versus inflammatory responses. Altered tryptophan catabolism is associated with inflammatory bowel disease, and changes in microbiota-mediated tryptophan metabolism shape systemic immune function.

• L-valineScientific

  L-Valine is documented as necessary for immunological function, including production of antibodies and regulation of immune cells. Dietary BCAA restriction has been shown to impair immune function. L-Valine derived from gut microbiota was found to protect against sepsis-induced intestinal injury in both human observational data and animal experiments, with L-valine levels inversely correlated with sepsis severity scores.

• LA (linoleic acid)Scientific

  LA and its metabolites modulate immune function through effects on eicosanoid production, lymphocyte activity, and inflammatory cytokine signaling. Clinical and observational evidence shows higher LA is inversely associated with pro-inflammatory cytokines (CRP, IL-6, TNF-α), and systematic reviews of RCTs find LA does not increase inflammation at typical intakes. LA-derived oxylipins regulate both pro- and anti-inflammatory immune pathways.

• lactobacillus acidophilusScientific

  L. acidophilus is one of the most studied probiotics for immune regulation. A dedicated meta-analysis of RCTs (n=1,171 subjects) found it significantly increased CD4+ T-cells, IgA, and the CD4+/CD8+ ratio while reducing IL-6 and TNF-α. It modulates both innate and adaptive immunity via Toll-like receptor engagement, dendritic cell activation, and cytokine modulation. Effects are broadly confirmed across multiple clinical populations including children, elderly, and immunocompromised individuals.

• lactobacillus brevisScientific

  L. brevis KB290 modulates systemic immune function by enhancing IFN-α production, augmenting influenza-specific IgA, and increasing splenocyte cytotoxic activity in animal models. L. brevis CD2 modulates local mucosal immunity via arginine deiminase-driven reduction of pro-inflammatory cytokines. Both strains thus engage the immune system through complementary innate and adaptive pathways.

• lactobacillus bulgaricusScientific

  Exopolysaccharides from L. bulgaricus OLL1073R-1 activate NK cells and induce IFN-γ in murine splenocytes. ADP-ribose from L. bulgaricus inhibits TNF-α-mediated cytotoxicity in vitro. In Crohn's disease patients, L. bulgaricus significantly lowered pro-inflammatory TNF-α in colonic mucosal samples. The WGO confirms immunostimulatory properties of L. bulgaricus-containing fermented dairy in controlled studies.

• lactobacillus caseiScientific

  L. casei has extensive clinical and mechanistic evidence for immunomodulation. It enhances macrophage and NK cell activity, increases secretory IgA, and modulates Th1/Th2/Treg cytokine balance. RCTs in children and adults document reduced infection incidence, improved vaccine responses, and modulation of inflammatory markers across multiple populations.

• lactobacillus crispatusScientific

  L. crispatus modulates innate mucosal immunity via surface layer proteins (SLPs) and exopolysaccharides that selectively engage anti-inflammatory receptors (DC-SIGN), shield TLR ligands, and suppress NF-κB activation. In clinical specimens, L. crispatus-dominated vaginal microbiomes correlate with lower pro-inflammatory cytokines (IL-1α, IL-1β, IL-8). A Lancet Microbe RCT confirmed that LACTIN-V reduced genital IL-1α and soluble E-cadherin significantly versus placebo.

• lactobacillus gasseriScientific

  L. gasseri SBT2055/paragasseri modulates immune function through activation of plasmacytoid dendritic cells (pDCs), induction of IgA in the small intestine, and elevation of NK cell activity. Two RCTs confirm that daily intake reduces common cold symptom incidence and improves salivary secretory IgA in healthy adults.

• lactobacillus jenseniiScientific

  L. jensenii has been studied as a mucosal immune modulator and as a delivery vector for HIV-inhibitory proteins. An engineered L. jensenii strain expressing cyanovirin-N reduced SHIV acquisition by 63% in a rhesus macaque repeated-challenge model. The species is also documented to modulate differentiation of monocytic precursors and forms part of the innate immune barrier of the female genital tract against HIV and other pathogens.

• lactobacillus paracaseiScientific

  L. paracasei is one of the most extensively studied probiotics for immune modulation. Multiple human RCTs demonstrate it enhances innate immunity (NK cell activity, phagocytosis) and adaptive immunity (IFN-γ, vaccine-driven antibody responses), and shifts dysregulated Th1/Th2 balance. It has been studied in healthy adults, elderly subjects, asthmatic children, and allergic rhinitis patients.

• lactobacillus plantarumScientific

  L. plantarum modulates innate and adaptive immunity in clinical studies, including IL-10 upregulation in inflammatory conditions, IgA modulation, and cytokine balance. It is among the most studied probiotic species for immune modulation.

• lactobacillus rhamnosusScientific

  Lactobacillus rhamnosus GG (LGG) has substantial clinical and mechanistic evidence supporting immune modulation. It stimulates innate and adaptive immune responses—including IgA, IgG, NK cell activity, and regulatory T-cell induction—via interactions with dendritic cells and pattern-recognition receptors. Multiple randomized controlled trials and meta-analyses show benefits in reducing upper respiratory tract infections and enhancing antibody responses to pathogens.

• lactobacillus salivariusScientific

  L. salivarius has demonstrated immunomodulatory effects in human RCTs. A phase II double-blind placebo-controlled trial in 40 healthy adults with L. salivarius CECT5713 found significant increases in NK cells, white blood cells, regulatory cytokine IL-10, and immunoglobulins M, A, and G. In vitro studies confirm strain-dependent modulation of Th1/Th2 cytokine profiles via macrophage and dendritic cell interactions.

• lactococcus lactisScientific

  L. lactis strain Plasma (LC-Plasma) directly activates human plasmacytoid dendritic cells (pDCs) via TLR9/MyD88 signaling, inducing type-I interferon production and activating adaptive immunity — demonstrated in a human clinical trial. Separately, GM L. lactis strains delivering IL-10, IL-1Ra, and other cytokines modulate mucosal immune responses in clinical-phase studies. Wild-type strains expand regulatory T cells and modulate Th1/Th2/Th17 balance in preclinical models.

• lactoferrinScientific

  Lactoferrin is a multifunctional iron-binding glycoprotein naturally present in milk and secretions of the immune system that exerts well-documented antimicrobial, anti-inflammatory, and immunomodulatory effects. Human clinical trials and meta-analyses confirm it can reduce systemic inflammatory biomarkers (notably IL-6) and improve immune cell function in adults. Evidence is strongest for reducing respiratory tract infection incidence in infants and children, while effects in adults are more modest and context-dependent.

• lactoperoxidaseScientific

  Lactoperoxidase is a recognized component of the innate mucosal immune system in humans and mammals. It is secreted by salivary, mammary, and respiratory mucosal glands and functions as a nonspecific first-line defense mechanism against bacteria, fungi, and viruses. Its role in innate immunity is well established in biochemical and immunological literature.

• lemonScientific

  Lemon is a recognized dietary source of vitamin C, an essential nutrient for multiple immune functions including natural killer cell activity, lymphocyte proliferation, neutrophil function, and interferon production. Clinical evidence documents that vitamin C supplementation reduces severity and duration of respiratory infections.

• lentinula edodes myceliaScientific

  LEM is an established oral immunomodulator with documented effects on dendritic cells, T-cells, NK cells, and macrophages. A human pilot study in gastrointestinal cancer patients showed improved IFN-γ production by CD4+, CD8+, and NK/NKT cells when LEM was added to chemotherapy. Lentinan derived from the same mushroom is approved in Japan as an immunostimulant.

• licorice rootScientific

  Glycyrrhizin and related compounds modulate immune function through anti-inflammatory (NF-κB, TNF-α suppression), antiviral, antihistaminic, and immunostimulating activities. A study published in Food Chemistry characterized licorice as having immunostimulating properties. Multiple clinical uses—from herpes management to antiviral hepatitis treatment—depend on immune modulation.

• lignansScientific

  Lignans modulate immune function primarily through inhibition of pro-inflammatory cytokine expression via NF-κB, JAK/STAT, and AP-1 pathways. Reductions in C-reactive protein have been documented in human trials. The gut microbiota-mediated conversion of lignans to enterolignans also produces immunomodulatory SCFAs. Antitumor immune effects have been documented in breast and prostate cancer cell lines.

• lilacScientific

  Immunomodulatory activity of S. vulgaris is documented in peer-reviewed preclinical studies. Extracts modulate cytokine production (TNF-α, IL-6, IL-8, TGF-β) in primary human immune cells (neutrophils, monocytes/macrophages). Multiple Syringa genus reviews confirm immunomodulatory pharmacological activity.

• lilyScientific

  Lily bulb polysaccharides are well-documented as immunomodulatory agents, with evidence of T-cell enhancement, immunomodulatory activity, and anti-tumor immune effects in multiple preclinical studies. The 2025 PMC systematic review lists immunomodulatory activity as a validated pharmacological property. No human immunological intervention trials have been published.

• limeScientific

  Lime's vitamin C and flavonoids support multiple branches of immune function, including maintenance of epithelial barriers, enhancement of phagocyte activity, and regulation of cytokine responses. A 2026 animal study demonstrated that citrus juice restored phagocytic index and reduced pro-inflammatory cytokines. Human data from vitamin C supplementation trials support reduced infection severity and duration.

• limoneneScientific

  Limonene exerts immunomodulatory effects including suppression of TH1 and TH2 cytokine production by stimulated T cells, inhibition of neutrophil and leukocyte chemotaxis, reduction of pro-inflammatory macrophage mediators, and regulation of IgE in allergic models. It also demonstrates antifungal and antibacterial activity relevant to immune defense. Effects span innate and adaptive immunity.

• lion's maneScientific

  Lion's Mane (Hericium erinaceus) contains bioactive polysaccharides — primarily β-glucans — and proteins shown in preclinical and in vitro studies to modulate immune function by enhancing macrophage activity, NK cell activity, and cytokine regulation. In vitro work using human peripheral blood mononuclear cells (PBMCs) has demonstrated measurable immunomodulatory effects. However, large-scale controlled human clinical trials specifically targeting immune outcomes are still limited, and the overall body of clinical evidence remains preliminary.

• lophatherum leafScientific

  L. gracile flavone C-glycosides modulate neutrophil-driven immune responses in human neutrophils, reducing oxidative bursts and NET formation. Extracts inhibit RSV and SARS-CoV-2 pseudovirus, supporting innate antiviral immunity. Anti-inflammatory effects via NF-κB suppression are documented in multiple studies. All evidence is preclinical.

• lotus seedScientific

  Lotus seed polysaccharides (LSPS) demonstrate immunomodulatory effects in H22 tumor-bearing mice, enhancing spleen and thymus indexes and elevating cytokines TNF-α and IL-2. Lotus seed protein hydrolysates activate mouse macrophages. No human immunological trials exist.

• luteinScientific

  Lutein modulates both innate and adaptive immunity, suppressing pro-inflammatory cytokine production while influencing antibody responses and lymphocyte populations. It inhibits IL-6, TNF-α, and IL-1β and has been shown in animal studies to enhance antibody responses to T-cell-dependent antigens. In humans, a 6-month supplementation trial found reductions in serum IL-1β and increases in antioxidant capacity and BDNF, indicative of immune-inflammatory modulation.

• luteolinScientific

  Luteolin, a dietary flavone found in celery, broccoli, and herbs, is well-documented in preclinical research as a multi-target immunomodulator. It suppresses key pro-inflammatory signaling cascades—NF-κB, MAPK/AP-1, JAK/STAT3, and NLRP3 inflammasome—and reduces secretion of cytokines including TNF-α, IL-1β, and IL-6. It also regulates adaptive immunity by balancing Th1/Th2 differentiation, promoting regulatory T cell function, and modulating macrophage polarization. Evidence is primarily from in vitro and animal studies, with limited but emerging clinical data; large-scale human trials are lacking.

• lycheeScientific

  Lychee extracts have demonstrated immunomodulatory activity in multiple in vitro and in vivo studies, including modulation of cytokine production (IL-6, TGF-β, TNF-α) in human clinical trials, antiviral effects against HSV-1 in vitro, and regulation of intestinal immune signaling (TLR-4, NLRP3). Lychee seed is cited in TCM pharmacology as possessing antiviral and immunomodulatory properties. Human clinical evidence for systemic immune outcomes remains limited.

• lycopeneScientific

  Lycopene modulates immune function by reducing oxidative stress in lymphocytes, inhibiting NF-κB-driven cytokine production, and reducing inflammatory biomarkers across multiple clinical studies. Cross-sectional data from NHANES III found decreased carotenoids including lycopene in individuals with elevated CRP. Clinical trials showing reductions in CRP, IL-6, and TNF-α support a systemic immunomodulatory role.

• magnesiumScientific

  Magnesium is essential for immune competence, serving as a cofactor in immune cell activation and inflammatory signaling. Magnesium deficiency promotes a pro-inflammatory state, increasing cytokines such as IL-1 and TNF-α. Clinical meta-analyses show magnesium supplementation produces a statistically significant reduction in CRP, supporting an anti-inflammatory effect.

• magnoliaScientific

  Magnolol and honokiol suppress both innate and adaptive immune overactivation: they reduce pro-inflammatory cytokines (TNF-α, IL-6, IL-1β, IL-8), inhibit NF-κB-driven immune activation, and block type 4 delayed hypersensitivity reactions mediated by T lymphocytes. These effects suggest immunomodulatory rather than purely immunosuppressive activity.

• maitake mushroomScientific

  Maitake mushroom (Grifola frondosa) has human clinical trial evidence supporting immunomodulatory activity, primarily attributed to its beta-glucan polysaccharides—notably the D-fraction. Multiple phase I/II trials have demonstrated measurable effects on innate and adaptive immune parameters, including NK cell activity, neutrophil and monocyte function, and antibody response. Evidence quality is moderate; trials are generally small and some lack placebo controls, but the direction of effect is consistent across studies.

• malabar nutScientific

  A. vasica demonstrates immunomodulatory properties through its secondary metabolites, and human trial data from the 2023 COVID-19 RCT shows support for immune-mediated viral clearance. Anti-inflammatory and antiviral mechanisms contribute to immune system activity.

• manganeseScientific

  The NIH ODS and peer-reviewed reviews confirm manganese's role in immune response via MnSOD-mediated protection of immune cells from oxidative burst, and via arginase activity in macrophage function. Manganese is recognized as essential for immune response.

• mangoScientific

  Mango provides two key immunonutrients: vitamin C (~60–67% DV per cup) and vitamin A (from beta-carotene). Vitamin C supports white blood cell production and function; vitamin A maintains mucosal immune barriers. Beta-carotene also functions as an antioxidant protecting immune cells from oxidative damage.

• mangosteenScientific

  Human RCTs on mangosteen-based beverages confirmed modulation of systemic inflammatory and immune markers including CRP, TNF-α, and cytokine levels without adverse effects on IgA, IgG, or IgM. A clinical trial in HPV-infected women showed normalization of immune markers (TRAIL, IL-2, TNF-α). Mangosteen xanthones have documented anti-inflammatory, antibacterial, antifungal, and antiviral activities.

• mannoseScientific

  D-mannose modulates immune function through a well-characterized mechanism: it promotes regulatory T cell (Treg) differentiation from naive CD4+ T cells by activating latent TGF-β via integrin αvβ8 upregulation and fatty acid oxidation-driven ROS. This has been confirmed in human cells in vitro and in multiple animal disease models. Mannose also shapes CD8+ T cell fate in cancer immunity and interacts with mannose receptors on macrophages and dendritic cells.

• maqui berryScientific

  Maqui berry anthocyanins modulate immune cell activity: they inhibit LPS-induced macrophage activation (reducing iNOS and TNF-α), and contain vitamin C and polyphenols that broadly support immune function. The 2026 systematic review noted emerging immunomodulatory properties. Traditional Mapuche use included maqui for bolstering general health and resistance.

• marjoramScientific

  Marjoram's broad antimicrobial (antibacterial, antifungal, antiviral) and anti-inflammatory properties constitute documented immune-relevant pharmacological activities. Its compounds terpinen-4-ol and thymol inhibit pathogen growth and modulate inflammatory immune responses.

• marshmallowScientific

  Marshmallow polysaccharides demonstrate immunomodulatory effects in vitro and in animal models, including macrophage activation, enhanced phagocytosis, increased T-lymphocyte counts, and cytokine modulation. In vitro studies show inhibition of TNF-α and IL-6 at diclofenac-comparable levels. These effects are documented in peer-reviewed research.

• mastic gumScientific

  Mastic gum modulates innate and adaptive immune pathways: it inhibits macrophage COX-2 and iNOS, suppresses NF-κB-driven cytokine production (TNF-α, IL-6, IL-8, IL-17A), and prolongs the life of oral polymorphonuclear leukocytes by inhibiting apoptosis. Human IBD studies link mastic to modulation of IL-17A immune response and altered fecal metabolomes. The EMA has recognized its anti-inflammatory therapeutic use.

• melaleuca alternifoliaScientific

  Terpinen-4-ol, the principal constituent of M. alternifolia oil, has been shown in human monocyte and macrophage studies to suppress production of key pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, PGE2) via interference with NF-κB and MAPK signaling pathways. These findings are from ex vivo/in vitro human cell studies rather than clinical immunology trials.

• melatoninScientific

  Melatonin has well-documented immunomodulatory effects supported by multiple human clinical trials and systematic reviews. It acts as an 'immune buffer'—stimulating immune responses under basal or suppressed conditions while suppressing pro-inflammatory cytokines during exacerbated inflammation. A 2021 PMC-indexed meta-analysis of clinical trials found that exogenous melatonin significantly reduced IL-1, IL-6, IL-8, and TNF levels in humans. Evidence strength is moderate: robust mechanistically, but many human trials are short-duration or small in scale.

• menthol oilScientific

  Menthol demonstrates immunomodulatory activity via anti-inflammatory cytokine suppression (TNF-α, IL-6) and antioxidant defense upregulation. Preclinical evidence is robust; clinical evidence is indirect through its recognized anti-inflammatory effects in GI and skin conditions.

• milk thistleScientific

  Silymarin has documented immunomodulatory activity, suppressing inflammatory cytokines and modulating T-cell activation markers. A PLoS One in vitro study using human immune cells—including from HIV-positive subjects—found that silymarin suppressed activation and exhaustion markers in CD4+ and CD8+ T cells and modulated pro-inflammatory cytokine release from monocytes.

• millet seedScientific

  Millet seed polyphenols and fiber support immune function through modulation of gut-associated lymphoid tissue and production of SCFAs that regulate mucosal immunity. Millet polyphenols exhibit anti-inflammatory effects by suppressing NF-κB-mediated cytokine production. Iron provision from pearl millet supports immune cell development and function in deficient populations.

• momordicaScientific

  Momordica charantia contains MAP30 and other ribosome-inactivating proteins with well-documented immunomodulatory and antiviral activity. In vitro studies show activity against HIV, herpes, HBV, and SARS-CoV-2. Immunostimulant properties have been described in folk medicine and confirmed preclinically.

• monk fruitScientific

  Monk fruit polysaccharides and mogrosides have documented immunomodulatory properties in preclinical research. A Springer 2024 animal study specifically investigated immune-enhancing activity of long-term monk fruit juice consumption and found enhanced immune factors and enrichment of immune-related gut flora. In vitro evidence shows mogrosides support immune organ function.

• monolaurinScientific

  Monolaurin modulates immune function via T-cell lipid dynamics, cytokine regulation, and antiviral/antibacterial activity against enveloped pathogens. A 2025 prospective human cohort of 2,712 healthcare workers found higher serum monolaurin significantly associated with lower COVID-19 risk. Animal studies show modulation of interferon pathways and attenuation of cytokine storm.

• morindaScientific

  Immunomodulation is a recognised pharmacological property of both M. officinalis and M. citrifolia. M. officinalis polysaccharides enhance immune function and are listed in the Shennong Bencao Jing for this purpose. M. citrifolia activates T and B lymphocytes and has been reviewed in clinical immunomodulatory applications.

• morusScientific

  Morus modulates immune system function through anti-inflammatory, antioxidant, and antimicrobial mechanisms. Human RCTs confirm reductions in inflammatory cytokines (TNF-α, IL-6, CRP). Mulberry flavonoids suppress NF-κB-driven immune overactivation while traditional use supports Morus as an immune-regulating herb in TCM.

• mugwortScientific

  Immunomodulatory activity is documented for A. vulgaris extracts and essential oils in preclinical studies. The plant suppresses pro-inflammatory cytokines (TNF-α) and displays antibacterial and antifungal activity. TCM use of moxibustion includes immune support as a traditional application. No human immunological RCTs exist.

• mulleinScientific

  Mullein's immunological relevance rests on documented antimicrobial, antiviral, and cytokine-modulating properties demonstrated in multiple in-vitro and pre-clinical studies. Flavonoids modulate TNF-α and IL-6, while saponins are noted for mild immune support. No human immunological trials exist.

• mustardScientific

  Mustard seed AITC and glucosinolate metabolites modulate immune function through NF-κB inhibition, Nrf2 activation, and broad-spectrum antimicrobial activity. The PMC review PMC12943160 confirms mustard seed's immunomodulatory properties. AITC has been shown to possess immune-boosting activity across multiple cell-based studies.

• myristoleateScientific

  CMO is proposed to function as an immune system modulator, either stimulating or downregulating immune activity to restore homeostasis. Mechanistically, N-myristoylation of intracellular signaling proteins affects cytokine receptor function, T-cell behavior, and hematopoietic differentiation. The Siemandi RCT supported immune-modulating effects in autoimmune arthritis populations.

• myrobalanScientific

  A pilot randomized, double-blind, placebo-controlled clinical study demonstrated that a standardized TC + Withania somnifera combination significantly enhanced immune function in adults. TC modulates innate and adaptive immunity through antioxidant, anti-inflammatory, and immunomodulatory properties.

• myrrhScientific

  Myrrh modulates immune function through multiple mechanisms: stimulating macrophage activity, immunomodulating via furanosesquiterpenes, and regulating pro-inflammatory cytokine production. Animal studies show myrrh elevates white blood cell counts before injury. The resin activates macrophages and exerts immunostimulant effects.

• N-acetyl-glucosamineScientific

  NAG modulates immune function through the hexosamine biosynthetic pathway, increasing N-glycan branching on immune cell receptors to regulate T-cell, B-cell, NK cell, dendritic cell, and macrophage activity. This mechanism has been demonstrated in human MS trials and multiple animal autoimmune models.

• NAC (N-acetyl cysteine)Scientific

  NAC supports immune function primarily by replenishing intracellular glutathione (GSH), the principal cellular antioxidant, and by suppressing pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) via NF-κB inhibition. Clinical evidence includes RCTs in autoimmune conditions (SLE), infectious disease, and chronic inflammatory states. Evidence strength varies by indication, and results across trials are sometimes conflicting.

• naringinScientific

  Naringin modulates innate and adaptive immune responses by suppressing NF-κB-driven pro-inflammatory cytokine production (TNF-α, IL-1β, IL-6, IL-23) and exhibiting immunomodulatory effects in human PBMC studies. An ex vivo study using cells from psoriasis patients demonstrated inhibition of multiple pro-inflammatory cytokines. It also inhibits osteoclast differentiation via immune-bone crosstalk.

• neem treeScientific

  The PMC review (2021) confirms neem extracts elevate CD4+/CD8+ T-cell counts and reduce proinflammatory cytokines TNF-α, IL-6, and NF-κB. Human RCT data show reduced systemic inflammation markers. Neem leaf is documented in PubMed as having immunomodulatory properties alongside antiviral, antibacterial, and antifungal activities.

• nettleScientific

  Nettle contains flavonoid glycosides that demonstrate immunomodulatory activity in vitro by stimulating neutrophil chemotaxis and intracellular lysis activity. A randomized double-blind trial for allergic rhinitis showed nettle extract significantly altered IFN-γ levels compared to placebo, indicating immune modulation. Nettle polysaccharides and lectins are also documented to modulate immune cell function in laboratory models.

• nicotinamide ribosideScientific

  In human RCTs, NR supplementation has reduced circulating pro-inflammatory cytokines in both healthy aged subjects and heart failure patients, with immune-modulatory effects linked to NAD+-dependent SIRT1 activation and NLRP3 inflammasome suppression. A clinical trial specifically assessing NR's effects on immunity (NCT02812238) has been registered and conducted.

• nopalScientific

  Nopal's polyphenols, betalains, and vitamins C and E exert documented immunomodulatory and anti-inflammatory effects across in vitro and animal studies. A human RCT found nopal extract significantly reduced inflammatory mediators associated with alcohol hangover, consistent with immune modulation. Reviews identify anti-inflammatory and antimicrobial properties as core activities of nopal bioactive compounds.

• nut grassScientific

  C. rotundus exhibits immunomodulatory, antimicrobial, antiallergic, antihistaminic, and anti-inflammatory effects that collectively implicate the immune system. The PMC 2023 study documents immunomodulatory activity. Antioxidant activity further supports immune defense.

• oatScientific

  Oat β-glucan is an immunomodulatory compound that activates macrophages, natural killer cells, and other innate immune cells via pattern recognition receptor binding. It modulates gut immune homeostasis through prebiotic activity and SCFA production, and avenanthramides regulate cytokine expression in immune-relevant pathways.

• oleanolic acidScientific

  OA modulates both innate and adaptive immunity. It suppresses innate immune overactivation (NF-κB, TLR4, macrophage activation), rebalances Th17/Treg adaptive immune responses, inhibits mast cell degranulation, and demonstrates antiviral activity affecting immune surveillance against viral pathogens.

• oleic acidScientific

  Oleic acid and its metabolite OEA modulate immune function through PPAR-α activation, suppression of NF-κB-driven cytokine production, and alteration of T-cell membrane composition. These effects are relevant to both systemic immunity (anti-inflammatory, anti-oxidative) and skin immunity (modulating wound and dermatitis responses). RCT evidence confirms OEA reduces inflammatory markers in humans.

• oliveScientific

  Olive leaf extract modulates immune function through antiviral, antimicrobial, anti-inflammatory, and phagocytosis-stimulating mechanisms. Human cell studies confirm immunomodulatory activity against multiple pathogens. A clinical trial in COVID-19 patients showed OLE improved immune-related clinical markers. Traditional use as an immune-supporting botanical in Mediterranean medicine is extensive.

• olive oilScientific

  EVOO polyphenols modulate both innate and adaptive immunity by suppressing pro-inflammatory cytokine production, inhibiting NF-κB activation, and supporting regulatory T-cell function. A PubMed review concluded olive polyphenols are potential candidates to combat chronic inflammatory states. Mediterranean diet with EVOO lowers risk of immune-mediated inflammatory diseases.

• omega-3 fatty acidsScientific

  Omega-3 fatty acids (primarily EPA and DHA) are well-documented immunomodulatory nutrients with substantial human clinical evidence. They suppress pro-inflammatory cytokines (TNF-α, IL-1β, IL-6), reduce eicosanoid synthesis from arachidonic acid, and serve as precursors to specialized pro-resolving mediators (resolvins, protectins, maresins) that actively terminate inflammation. Clinical trials and meta-analyses demonstrate measurable effects on immune cell populations, inflammatory biomarkers, and outcomes across autoimmune, surgical, and infectious disease contexts.

• omega-6 fatty acidsScientific

  Omega-6 PUFAs, especially AA and LA, are essential structural and signaling components of immune cells, required for normal immune function. AA-derived eicosanoids regulate immune cell activation, Th1/Th2 balance, and inflammation resolution. Both deficiency and excess of omega-6 PUFAs alter immune function: low intake enhances certain immune functions while high intake may suppress them. GLA and its metabolites have demonstrated immunomodulatory effects in both autoimmune and allergic contexts.

• omega-9 fatty acidsScientific

  Omega-9 oleic acid modulates immune function by reducing pro-inflammatory cytokine production, suppressing neutrophil influx, promoting anti-inflammatory macrophage phenotypes, and activating PPAR-γ. These effects collectively reduce excessive immune activation while supporting appropriate immune resolution.

• onionScientific

  Onion stimulates the immune system through multiple mechanisms including natural killer cell activation, lymphocyte proliferation, and modulation of cytokine networks. The sulfur compounds and quercetin in onion provide broad-spectrum antimicrobial activity against bacteria, fungi, and viruses. Multiple pharmacological reviews confirm 'immunoprotective' activity as a documented property of A. cepa.

• ophiopogonScientific

  Ophiopogon japonicus polysaccharides (OJPs) are well-characterized immunomodulatory agents, stimulating macrophage activation, phagocytosis, and nitric oxide release. Immunomodulatory activity is one of the most consistently documented pharmacological properties of OJPs across multiple preclinical studies.

• ophiopogon rootScientific

  Ophiopogon root polysaccharides have demonstrated immunomodulatory activity in multiple preclinical studies, including activation of macrophages and T-lymphocytes, and regulation of cytokine production. O. japonicus is documented in PubMed-indexed reviews as having immunomodulatory activity among its principal pharmacological properties. Ophiopogonin D also demonstrates immune regulatory effects.

• orangeScientific

  Orange is one of the richest dietary sources of vitamin C, which is essential for multiple immune functions including neutrophil chemotaxis, lymphocyte proliferation, and antibody production. Clinical evidence from Cochrane-level reviews confirms that regular vitamin C supplementation reduces cold duration and supports immune defence, particularly in physically stressed individuals.

• oreganoScientific

  Oregano essential oil modulates immune function through multiple mechanisms: antimicrobial elimination of infectious challenges (reducing pathogen burden on immune resources), anti-inflammatory suppression of dysregulated cytokines (TNF-α, IL-6, IL-1β), and antioxidant protection of immune cells. Carvacrol also demonstrates immunomodulatory activity in human skin cell models and animal studies. The compound has anti-allergic properties documented in the literature.

• oregon grapeScientific

  M. aquifolium alcoholic extracts demonstrate immunostimulating activity in phagocytosis assays in vitro. Berberine enhances immune cell function and inhibits bacterial adherence, reducing infection load. The antimicrobial alkaloids target multiple pathogens relevant to immune challenges including E. coli, P. acnes, Candida, and Streptococcus pyogenes. PeaceHealth cites berberine's ability to enhance immune cell function.

• oriental arborvitaeScientific

  P. orientalis polysaccharides have documented immunomodulatory activity, and the plant's antimicrobial, anti-inflammatory, and antioxidant properties collectively support immune function. Systematic reviews confirm immunological activity among the pharmacological properties of its polysaccharide fraction. Preclinical studies on macrophage activation and inflammatory cytokine modulation are the primary evidence base.

• oryzaScientific

  Rice bran (Oryza sativa) has immunostimulatory and immunomodulatory properties, supported by human RCT data showing increased interferon-gamma activity with fermented rice bran supplementation, and clinical evidence of reduced enteric pathogen burden and improved gut immunity in infants.

• oyster mushroomScientific

  Pleuran—the unique insoluble β-1,3/1,6-D-glucan extracted exclusively from P. ostreatus—has been tested in multiple human RCTs and shown to reduce respiratory tract infection incidence in children, improve NK cell activity in athletes, and reduce HSV-1 symptom duration. A large multicentre open-label study (n=1,030 children) confirmed significant reductions in RTI frequency and duration.

• PABA (para-aminobenzoic acid)Scientific

  PABA has been established as an inducer of endogenous interferon-alpha/beta and functions as an immunomodulator. In vitro and animal studies show it induces interferon production in human peripheral blood immunocytes and in mice. This discovery led to the development of the antiviral ophthalmic drug Actipol. PABA may also promote anti-inflammatory macrophage polarization.

• paederia foetidaScientific

  P. foetida modulates multiple immune mediators in preclinical models, suppressing NF-κB, TNF-α, IL-1β, IL-6, and COX-2 while activating Nrf2/HO-1 antioxidant defenses. Anti-inflammatory, antioxidant, and anthelmintic activities collectively support immune system interaction.

• palm oilScientific

  Palm tocotrienol-rich fraction (TRF) has demonstrated immune-enhancing activity, including modulation of lymphocyte responses and cytokine profiles. A registered clinical trial is actively investigating TRF's immunomodulatory effects following influenza vaccination in healthy adults. Red palm oil's provitamin A also supports innate immune function by maintaining mucosal barriers.

• palmitateScientific

  Vitamin A palmitate is fundamental to both innate and adaptive immunity. It maintains mucosal barrier integrity, supports T-cell differentiation and function, and is required for production of antibodies and effective immune responses. WHO/UNICEF-endorsed supplementation reduces child mortality from infectious diseases.

• palmitic acidScientific

  Palmitic acid directly activates human innate immune cells via TLR4, functioning as an endogenous TLR4 ligand. This triggers pro-inflammatory responses in human dendritic cells, macrophages, and monocytes, including NF-κB activation and secretion of IL-1β, IL-6, and TNF-α. It also promotes dendritic cell maturation and modulates macrophage inflammatory signaling through nucleotide sugar metabolism.

• palmitoleic acidScientific

  POA modulates immune function by reducing lymphocyte proliferation and suppressing pro-inflammatory cytokine production. It suppresses Th1 and Th17 responses and modulates co-stimulatory and apoptotic molecules in human lymphocytes.

• papayaScientific

  Fermented papaya preparation (FPP) has been studied clinically for immune function, with evidence of restored age-related immune declines and immunomodulatory effects including NK-cell activity. In dengue patients, papaya leaf extract increased platelet and WBC counts and modulated pro-inflammatory cytokines in RCT evidence. Papaya's vitamin C content is an established immune cofactor.

• parsleyScientific

  Parsley is a rich source of vitamins C and A, both essential for immune cell function and mucous membrane integrity. Flavonoids contribute additional immunomodulatory and anti-inflammatory effects. Dietary intake of parsley at culinary amounts provides immunologically relevant micronutrient doses.

• partheniumScientific

  Feverfew's principal bioactive, parthenolide, is a well-characterised immunomodulator that suppresses NF-κB, reduces pro-inflammatory cytokine production (TNF-α, IL-1, IL-6, IL-8, IL-12), inhibits neutrophil function, and modulates mast cell degranulation. A human RCT assessed immunological markers following 250 mg/day T. parthenium for 2 weeks.

• paw pawScientific

  Carica papaya leaf extract demonstrates immunomodulatory effects including improved platelet counts in dengue thrombocytopenia, increased phagocytic activity of polymorphonuclear leukocytes, and modulation of cytokines (IL-6, IL-8, TNF-α). Clinical studies in dengue fever and post-COVID recovery support immune-boosting and immune-balancing effects.

• peachScientific

  Peach extracts have demonstrated immunomodulatory activity including inhibition of allergic inflammatory responses and antioxidant protection of immune tissues. Anti-inflammatory properties via NF-κB inhibition and cytokine modulation are documented in preclinical models.

• pearScientific

  Pear provides vitamin C and a range of polyphenols (quercetin, chlorogenic acid, catechins) that support immune defense through antioxidant protection and anti-inflammatory modulation. Pear polyphenols modulate macrophage activity and have demonstrated immunomodulatory effects in cell models. Quercetin and rutin in pears have potential for modulating allergic immune responses via mast cell inhibition.

• pectinScientific

  Pectin modulates immune function through prebiotic effects that shift microbiota toward immunoprotective profiles, SCFA production that regulates innate immune cell activity, and direct interaction with immune receptors. In vitro evidence shows pectin reduces macrophage-mediated pro-inflammatory cytokine production.

• peonyScientific

  TGP from Paeonia lactiflora is one of the best-characterized immunomodulatory herbal extracts, with clinical application in multiple autoimmune diseases. It balances immune function by modulating dendritic cells, Th1/Th17 activity, and inflammatory cytokine networks.

• PEP (prolyl endopeptidase)Scientific

  PEP degrades the T-cell-activating epitopes within gliadin peptides before they reach the intestinal mucosa, thereby interrupting the adaptive immune response central to celiac disease and gluten sensitivity. Studies using patient-derived T cells confirm that PEP-treated gluten is unable to stimulate gluten-specific T cell proliferation. Multiple clinical trials have tested this immunological rationale in human subjects.

• peppermintScientific

  Peppermint demonstrates immunomodulating activity in animal models and in vitro, including documented anti-inflammatory effects via TRPM8 channel activation and suppression of inflammatory mediators. A PubMed-indexed review confirms animal model studies demonstrate immunomodulating actions. In vitro, menthol suppresses production of inflammatory mediators from human monocytes at clinically relevant concentrations.

• peptidaseScientific

  Oral peptidase/proteolytic enzyme supplementation has demonstrated immunomodulatory effects in human clinical studies, including alterations in T-cell activity, cytokine profiles, and degradation of circulating immune complexes. Memorial Sloan Kettering cites clinical studies showing immunomodulatory effects in healthy volunteers given oral proteolytic enzymes. Mechanistic evidence implicates protease-activated receptor-2 (PAR-2) on immune cells.

• perillaScientific

  Perilla frutescens extracts modulate both innate and adaptive immune responses—reducing pathological Th2 cytokines (IgE, IL-4, IL-5) in allergic conditions while upregulating phagocytic and T-cell receptor signaling. Human clinical trials confirm immune-modulating benefits in allergic rhinoconjunctivitis. Rosmarinic acid suppresses mast cell, eosinophil, and neutrophil activation.

• phellodendron amurenseScientific

  P. amurense bark is one of the most studied TCM plants for immune modulation. Phellodendrine and magnoflorine isolated from P. amurense are the most potent suppressors of cellular immune responses among eight TCM herbs tested, suppressing delayed-type hypersensitivity and graft-versus-host reactions in animal models. Berberine has both antimicrobial and immunomodulatory properties.

• phytosterolsScientific

  Beta-sitosterol and its glucoside (phytosterolins) have demonstrated immune-modulatory activity on human lymphocytes in clinical studies. Trials in HIV and pulmonary tuberculosis patients showed maintenance of CD4 cell counts, improved Th1/Th2 balance, and enhanced NK cell activity. Anti-inflammatory immune effects are also documented.

• picrorhiza kurroaScientific

  P. kurroa extracts exhibit well-characterized immunomodulatory activity, stimulating both humoral and cell-mediated immunity in animal models. Picroliv also has documented anti-allergic and immunostimulant properties. Multiple peer-reviewed preclinical studies support this, and P. kurroa is regarded in Ayurveda as a primary immune tonic.

• pineScientific

  Pine bark extract has demonstrated immunostimulant effects in preclinical studies, including enhancement of antioxidant enzymes and glutathione levels. It inhibits pro-inflammatory cytokines (IL-1β, TNF-α) via NF-κB suppression. Traditional use across many cultures employed pine preparations to fight infections. Clinical studies include asthma and allergy modulation where Pycnogenol reduced immune-mediated inflammatory markers.

• pine barkScientific

  Pycnogenol modulates immune function through anti-inflammatory inhibition of NF-κB, TNF-α, IL-1β, and IL-6, and by attenuating mast cell histamine release. RCTs confirm reduced inflammatory biomarkers across multiple conditions. The extract downregulates T-cell adhesion to keratinocytes via ICAM-1 inhibition, relevant to immune-mediated skin and inflammatory conditions.

• pineappleScientific

  Bromelain has documented immunomodulatory activity, confirmed in a placebo-controlled human RCT. It modulates T cell function, dendritic cell activity, and cytokine profiles. Pineapple's vitamin C directly supports immune cell function and antibody production. A Philippine study found pineapple consumption improved immunological markers in school children.

• pistacia integerrima gallScientific

  Preclinical studies demonstrate immunomodulatory activity of P. integerrima gall extracts, including mast cell stabilization, downregulation of Th2 cytokines (IL-4, IL-5, IL-13), and modulation of NF-κB pathways. An ovalbumin mouse asthma model showed significant immunomodulation at 200 mg/kg. The 2026 Springer review explicitly characterizes the galls as immunomodulatory.

• plant sterolsScientific

  Plant sterols have documented immunomodulatory properties, including modulation of T-lymphocyte activity and natural killer cell function at low concentrations. Clinical studies have explored their role in immune stress in marathon runners and in conditions including HIV and rheumatoid arthritis, though the evidence base is smaller and more heterogeneous than that for cholesterol lowering.

• plantagoScientific

  Plantago major contains immunostimulatory pectic polysaccharides and immunomodulatory compounds (aucubin, plantamajoside). Clinical-level evidence for antiviral effects exists. Psyllium (P. ovata) is documented to exhibit immunomodulatory and antiviral effects. ESCOP in vitro data confirm immunostimulant activity for P. lanceolata.

• plantainScientific

  Immunostimulatory activity of P. major is confirmed in experimental research, with pectic polysaccharides and aucubin identified as key immunomodulatory agents. Psyllium consumption produces immunomodulatory effects through SCFA-mediated modulation of immune cell function. Anti-inflammatory effects (COX inhibition, histamine suppression, NF-κB inhibition) further support immune system modulation.

• platycodonScientific

  Platycodon polysaccharides and saponins are established immunomodulators, enhancing macrophage activity, T cell function, NK cell activity, and immunoglobulin production. A human clinical trial (KCT0005945) investigated PG extract for immune enhancement. Both immunostimulatory and immunoregulatory (Th1/Th2 balancing) effects are documented.

• platycodon rootScientific

  Platycodon root exhibits bidirectional immunomodulatory effects: stimulating macrophage and T-cell activity while suppressing excessive inflammatory cytokines via NF-κB, MAPK, and PI3K/AKT pathways. An 8-week placebo-controlled human RCT (KCT0005945) demonstrated immune function enhancement with red platycodon root extract.

• polygalaScientific

  Bioactive compounds from P. tenuifolia suppress pro-inflammatory cytokine production (IL-12p40, IL-6, TNF-α) in immune cells (dendritic cells, macrophages) in vitro, and xanthone constituents inhibit influenza A neuraminidases. Preclinical evidence supports immunomodulatory and anti-inflammatory activity of PT extracts.

• polygala rootScientific

  Polygala root constituents inhibit pro-inflammatory cytokine production (IL-12 p40, IL-6, TNF-α) in immune cell assays, and a 2024 Frontiers review formally identified immune system protection as a pharmacological category. These are documented in PMC-indexed peer-reviewed studies.

• polyporusScientific

  P. umbellatus polysaccharides are well-characterized immunomodulators that activate macrophages via TLR4/NF-κB, enhance NK cell activity, increase lymphocyte proliferation, and have supported clinical immune enhancement in hepatitis B patients in China.

• pomegranateScientific

  Pomegranate polyphenols modulate immune function via NF-κB inhibition, reduction of pro-inflammatory cytokines (TNF-α, IL-6, CRP), and enhancement of antioxidant enzymes. RCTs in RA and IBD patients document immunomodulatory effects. Pomegranate also exhibits antimicrobial properties against a range of bacterial and fungal pathogens.

• pomeloScientific

  Pomelo is one of the richest dietary sources of vitamin C (~129% DV/serving), which is essential for white blood cell production and activity. Naringenin and naringin enhance innate immune responses and exhibit broad-spectrum antimicrobial activity. Pomelo's antioxidant compounds protect immune cells from oxidative damage during infection responses.

• pregnenoloneScientific

  Pregnenolone is synthesized in lymphocytes and acts as an anti-inflammatory molecule within the immune system, suppressing TLR2/4-mediated pro-inflammatory cytokine production (TNF-α, IL-6) in macrophages and microglia. Decreased pregnenolone levels are observed in neuroinflammatory diseases.

• prickly pear cactusScientific

  Prickly pear phenolics, flavonoids, and betalains have demonstrated immunomodulatory and anti-inflammatory activity in multiple experimental models. Prickly pear peel extracts promoted innate immune function in cell models. Human evidence is indirect via antioxidant and anti-inflammatory clinical studies.

• privetScientific

  Ligustrum lucidum modulates immune function through multiple mechanisms demonstrated in preclinical studies, including enhanced lymphocyte proliferation, macrophage activation, and cytokine regulation. One small human RCT used a ligustrum-containing formula in cancer patients with immunosuppression. The 2020 Chinese Pharmacopoeia documents immunodeficiency treatment as an application.

• propionic acidScientific

  Propionate acts as a systemic immunomodulator via HDAC inhibition and FFAR2/FFAR3 signaling, promoting regulatory T cell differentiation, suppressing Th1/Th17 responses, and modulating macrophage polarization toward anti-inflammatory phenotypes. These effects are clinically documented in MS patients and supported by mechanistic studies in IBD models. SCFAs including propionate regulate the activation and recruitment of neutrophils, macrophages, and T cells.

• propolisScientific

  Propolis has well-documented immunomodulatory properties supported by in vitro, in vivo, and clinical human studies. Its bioactive compounds — primarily flavonoids (quercetin, kaempferol, pinocembrin) and phenolic esters (CAPE) — modulate cytokine production, macrophage activity, NK cell function, and inflammatory signaling pathways. Meta-analyses of randomized controlled trials have confirmed statistically significant reductions in key pro-inflammatory markers (IL-6, TNF-α, CRP) following propolis supplementation. Evidence strength is moderate; most trials are small and heterogeneous in propolis type and dose.

• pruneScientific

  Prune polyphenols modulate immune-relevant inflammatory pathways, suppressing TNF-α, IL-1β, and CRP in human trials. Gut microbiome enrichment of Lachnospiraceae by prune fiber correlates with lower systemic IL-1β levels. In vitro, dried plum polyphenol extracts suppress LPS-induced pro-inflammatory mediator production in macrophages.

• prunusScientific

  Prunus species exhibit documented immunomodulatory activity through polyphenol and triterpene-mediated regulation of pro-inflammatory cytokines (IL-6, TNF-α, IL-1β) and prostaglandins. A 2024 in-vitro study with P. africana extract in LPS-stimulated human PBMCs confirmed significant IL-6 reduction. P. domestica polyphenols inhibit LPS-stimulated nitrite, IL-1β, and PGE2 in activated macrophages.

• pterocarpus marsupiumScientific

  P. marsupium modulates immune-related inflammatory pathways, suppressing TNF-α, IL-6, and caspase-3 in preclinical models. Its polyphenols have broad immunomodulatory effects documented in pharmacological reviews.

• pumpkinScientific

  Pumpkin flesh and seeds together provide vitamins A, C, and E, zinc, iron, selenium, and beta-carotene—a combination of micronutrients with well-established, independently verified roles in innate and adaptive immune function. Cleveland Clinic and WebMD, citing primary research, confirm that pumpkin contains an immune-supportive micronutrient profile.

• punarnavaScientific

  B. diffusa has documented immunomodulatory activity, with the alkaloid punarnavine shown to enhance stem cell proliferation, differentiation, and antibody formation in BALB/c mouse models. Multiple phenolics and flavonoids also enhance total white blood cell counts. Traditional Ayurvedic Rasayana classification implies immune enhancement.

• purslaneScientific

  Purslane demonstrates immunomodulatory effects through multiple mechanisms: clinical trials confirm reductions in CRP and NF-κB; in vitro studies show polysaccharides stimulate lymphocyte proliferation; and animal studies document modulation of cytokines including TNF-α, IL-6, and IL-10. Anti-inflammatory and antioxidant properties are foundational to its immune activity.

• quercetinScientific

  Quercetin is a dietary flavonol with well-documented immunomodulatory and anti-inflammatory activity supported by multiple human clinical trials. Its key mechanisms include inhibition of NF-κB signaling, suppression of pro-inflammatory cytokines (TNF-α, IL-6, IL-1β), and inhibition of mast cell degranulation. Clinical evidence is promising but mixed, with effects appearing most consistent in specific subpopulations or when using enhanced-bioavailability formulations.

• quillajaScientific

  Quillaja-derived saponins, particularly QS-21, are among the most extensively clinically validated vaccine adjuvants, with use in over 80 human clinical trials. The saponins activate antigen-presenting cells, stimulate cytokine production, and drive both Th1 and Th2 immune responses. This represents the strongest body of clinical evidence for any Quillaja application.

• quinoaScientific

  Quinoa's protein hydrolysates and peptides demonstrate immunomodulatory effects including cytokine regulation and macrophage activation modulation in vitro. Quinoa polyphenols and saponins exhibit anti-inflammatory and antioxidant effects protecting immune cells from oxidative stress. Gut microbiota modulation by quinoa fiber and polysaccharides supports immune homeostasis, as approximately 70% of immune activity is gut-associated.

• radishScientific

  Radish contributes to immune function through its vitamin C content (supporting white blood cell production), documented antimicrobial properties of its glucosinolate-derived isothiocyanates, and the antifungal defensin protein RsAFP2. Traditional use across multiple systems designates it as useful for infection-prone states.

• raspberryScientific

  Raspberry polyphenols modulate immune signaling pathways in vitro and in animal studies, suppressing NF-κB, MAPK, JAK-STAT, and pro-inflammatory cytokines (IL-6, TNF-α, IL-1β). Raspberry fruit contains significant vitamin C, which is essential for immune function. A 2020 RCT found that 8 weeks of raspberry consumption produced significant gene expression changes in immune-metabolic pathways. Berry consumption trials in humans have also documented reductions in inflammatory cytokines.

• rehmanniaScientific

  Rehmannia modulates both innate and adaptive immune functions, enhancing dendritic cell and lymphocyte activity, regulating Th17/Treg balance, and suppressing mast cell-mediated allergic inflammation. The ScienceDirect overview explicitly identifies the immune system as a primary pharmacological target. Polysaccharides and catalpol from Rehmannia are the key immune-modulating constituents.

• rehmannia glutinosaScientific

  R. glutinosa has documented immunomodulatory effects including increasing leucocyte production, enhancing B-cell immunity, and modulating T/B lymphocyte balance. Polysaccharides enhance immune function; the 2018 anti-aging study showed significantly enhanced B-cell immunity in aged mice. It is listed in the Pharmacopoeia of China for immunoenhancement.

• reishi mushroomScientific

  Reishi mushroom (Ganoderma lucidum) has human clinical trial evidence supporting immunomodulatory activity. Its primary bioactive compounds—β-glucan polysaccharides and triterpenoids—have been shown in randomized controlled trials to significantly increase circulating T-lymphocyte, CD4+, CD8+, and natural killer (NK) cell counts. Evidence is strongest for cellular immune enhancement; effects on inflammatory markers in broader populations remain inconsistent across trials.

• resveratrolScientific

  Resveratrol, a polyphenolic stilbene found in red grapes and other plants, has documented immunomodulatory effects supported by both in vitro, animal, and human clinical data. It acts on key immune signaling pathways—particularly NF-κB and MAPK—to suppress pro-inflammatory cytokines such as TNF-α, IL-1β, IL-6, and IL-8. Human clinical trials have shown measurable changes in circulating immune cell subsets and inflammatory markers following supplementation, though effect sizes are modest and bioavailability remains a limiting factor. Clinical evidence currently supports an anti-inflammatory role rather than broad immune enhancement, and no definitive treatment recommendations have been established for any specific immune-related condition.

• rhodiolaScientific

  Multiple research lines identify Rhodiola rosea as an immunomodulator, with pre-clinical evidence of enhanced immune cell activity and one human study showing antiviral activity following marathon running. The PMC 2024 PPPM review confirmed immune regulatory effects in non-clinical and clinical studies. The immunostimulating potential of Rhodiola is also documented in a dedicated PMC review (2018).

• rhubarbScientific

  Rhubarb modulates immune responses through multiple mechanisms including reducing inflammatory cytokines, balancing T-helper cell populations, and modulating gut microbiota. In sepsis models and clinical contexts, rhubarb maintained immune balance and reduced SIRS-associated immunopathology. Multiple systematic reviews confirm immune-modulating activity.

• rhubarb rootScientific

  Rhubarb root modulates immune function in multiple documented ways. Lab data show decreased isolated immune cell activity; clinical meta-analyses document reduced systemic inflammatory markers in sepsis and SAP; and ulcerative colitis trials show immunological normalization of the hypercoagulable state.

• roseScientific

  Rosehip is a premier plant source of vitamin C, which supports immune cell production and function. Rosehip has demonstrated immunomodulatory properties in clinical and mechanistic studies, including stimulation of white blood cell production and modulation of inflammatory immune responses in autoimmune conditions like rheumatoid arthritis.

• rose hipsScientific

  Rose hips are one of the richest natural sources of vitamin C, a key regulator of immune cell function and antioxidant defense. Clinical evidence supports improved antioxidant status in healthy adults with rose hip supplementation. Vitamin C's roles in white blood cell production and function are well-established, and rose hip polyphenols and carotenoids provide additional immunomodulatory support.

• rosemaryScientific

  Rosemary's bioactives—particularly rosmarinic acid—modulate immune function by suppressing pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) and inhibiting NF-κB, a master regulator of immune inflammatory responses. Human clinical evidence from the RA RCT demonstrates significant immunomodulatory effects on CRP and inflammatory markers in vivo.

• rosmarinic acidScientific

  Rosmarinic acid is an established immunomodulator, suppressing NF-κB-driven cytokine production, inhibiting complement pathway activation, inducing apoptosis of activated T cells (demonstrated in human RA patient cells), suppressing IgE-mediated mast cell and basophil responses, and modulating Th1/Th2 balance. These effects have been validated in human cell studies and multiple human clinical trials.

• royal jellyScientific

  A double-blind RCT found protease-treated RJ (1,200 mg/day, 4 weeks) increased hematopoietic stem cells in peripheral blood in subjects without acute illness. RJ enhanced PBMC proliferation and modulated cytokines in ex vivo human cell studies. Immunomodulatory activity is also documented in multiple animal and in vitro models.

• rubia cordifoliaScientific

  R. cordifolia is recognized in Ayurveda as an immune regulator, and preclinical evidence supports immunomodulatory activity via modulation of macrophage function, cytokine suppression (TNF-α, IL-6, IL-1β), and NF-κB pathway inhibition. Its anti-platelet activating factor property is relevant to allergic immune responses. Lead nitrate toxicity studies showed R. cordifolia preserved macrophage viability, phagocytic index, and serum immunoglobulin levels.

• rutinScientific

  Rutin modulates multiple arms of immunity: it suppresses pro-inflammatory cytokine production from human macrophages, inhibits mast cell activation relevant to allergic immunity, modulates Th1/Th2 balance, and exerts NF-κB-dependent immunomodulatory effects documented in human and animal studies.

• ryeScientific

  Rye's bioactive compounds—benzoxazinoids, alkylresorcinols, and fermentable fiber—modulate immune function through anti-inflammatory signaling and SCFA-mediated gut-immune crosstalk. SCFA from rye fermentation support intestinal immune homeostasis. Rye's secalin protein also directly activates the adaptive immune response in celiac disease, demonstrating a clinically relevant immune system interaction.

• saccharomyces boulardiiScientific

  Saccharomyces boulardii exerts well-documented immunomodulatory effects on the gut-associated immune system, supported by multiple clinical trials and mechanistic reviews. It down-regulates pro-inflammatory cytokines (TNF-α, IL-8) via NF-κB and MAPK pathway inhibition while up-regulating anti-inflammatory mediators (IL-10, PPAR-γ) and stimulating secretory IgA production at mucosal surfaces. Clinical evidence is strongest for immune-mediated protection against antibiotic-associated diarrhea and infectious gastroenteritis, with meta-analyses confirming significant efficacy across diverse populations.

• safflowerScientific

  Safflower flavonoids exhibit immunomodulatory effects, including regulation of inflammatory cytokines and modulation of gut microbiota-mediated immune responses. Research demonstrates that safflower polysaccharides and flavonoids can enhance immune function by modulating short-chain fatty acid production and gut microbiota. Vitamin E content in safflower oil is documented as an immune-supportive nutrient. Safflower flavonoids inhibit NF-κB-mediated inflammatory signaling and reduce pro-inflammatory cytokines (IL-6, TNF-α, IL-1β).

• sageScientific

  Sage extracts modulate immune function by reducing pro-inflammatory cytokines (TNF-α, IL-12) across multiple human cell models, increasing antioxidant defenses in human lymphocytes, and demonstrating antimicrobial activity against a broad range of pathogens. Immunomodulatory effects have been confirmed in human cells.

• sarsaparillaScientific

  Smilax glabra rhizome has documented immunomodulatory activity in preclinical studies, classified by MSKCC as immunostimulatory. Astilbin specifically has been shown to suppress abnormal T-cell activation while preserving baseline immune function. The PMC review of SGR lists immunomodulation as one of its four primary pharmacological functions.

• schisandraScientific

  Schisandra activates Nrf2 and inhibits NF-κB and MAPK pathways, modulating innate immune responses. Animal studies show it reduces stress-induced IL-1, IL-2, and IL-6 dysregulation and partially restores immune function. TCM lists immune stimulation as a traditional application. Antifungal activity against all strains tested was documented in a comparative TCM study.

• schisandrinsScientific

  Schisandrin is documented to have immunomodulatory properties in the comprehensive PMC and pharmaceutical reviews. Schisandrin C enhances Type I IFN response activation for antitumor immunity. Schisandrin B modulates TLR4 and macrophage signaling. Traditional TCM use for immune conditions is also well established.

• schizonepetaScientific

  Extensive preclinical data confirm Schizonepeta modulates multiple immune pathways: NF-κB, MAPK, Th1/Th2 cytokine balance, mast cell degranulation, and antiviral interferon induction. The 2025 systematic review synthesized 13 studies confirming immunomodulatory mechanisms. No human immunological trials exist.

• sclerotiumScientific

  The beta-glucan polysaccharides of Poria cocos sclerotium are established immunomodulators, activating macrophages, NK cells, and dendritic cells via Dectin-1, TLR-2, and complement receptor 3. Immunomodulation is among the best-documented pharmacological effects with both preclinical and some clinical support.

• scrophularia rootScientific

  Immunomodulatory activity is a documented pharmacological property of S. ningpoensis root, with evidence of immune enhancement from in vivo studies. S. ningpoensis polysaccharides significantly increased thymus and spleen indices in tumour-bearing mice. S. buergeriana demonstrated immune-enhancing effects in in vitro and in vivo models.

• secoisolariciresinol diglucosideScientific

  SDG modulates immune function by suppressing pro-inflammatory cytokine production (TNF-α, IL-6, interferon-γ, CRP), reducing macrophage infiltration, and dampening NF-κB–driven immune signaling across multiple tissue types. In human RCT data, SDG reduced CRP and IL-6 in type 2 diabetics. It also inhibits apoptosis of immune-related endothelial and cardiomyocyte cells exposed to inflammatory stimuli.

• seleniumScientific

  Selenium is an essential trace element that, acting through selenoproteins, plays a well-documented role in regulating both innate and adaptive immune responses. Adequate selenium is required for the activation, proliferation, and differentiation of immune cells, including T cells, B cells, and natural killer (NK) cells. Clinical trials and systematic reviews confirm measurable immunological effects, though the evidence also shows that supplementation beyond adequate status yields inconsistent benefits and is context- and dose-dependent.

• selenomethionineScientific

  Selenium is recognized as an essential micronutrient for correct immune system functioning, and selenomethionine as its primary organic supplemental form modulates both innate and adaptive immunity through selenoproteins. It suppresses the TLR4/NF-κB pathway, reduces pro-inflammatory cytokines, and promotes macrophage polarization toward the anti-inflammatory M2 phenotype. Clinical evidence comes primarily from its well-documented reduction of thyroid autoantibodies in Hashimoto's thyroiditis.

• sesameScientific

  Sesame compounds (sesamol, sesame essential oil) modulate macrophage and dendritic cell pro-inflammatory function and promote Th2 immune responses. Sesame seeds are rich in zinc and selenium — essential for immune cell production and function. Clinical trial data confirm improvements in antioxidant enzyme activity (SOD, CAT), protecting immune cells from oxidative damage.

• shea butterScientific

  Shea butter's triterpene constituents modulate innate immune signaling in the skin and macrophages, suppressing excessive NF-κB-driven inflammatory responses and reducing pro-inflammatory cytokine production. This immune-modulatory activity is relevant to inflammatory skin conditions with a dysregulated cutaneous immune response, such as atopic dermatitis.

• shepherd's purseScientific

  Multiple in vitro studies demonstrate immunologically relevant activities of Capsella bursa-pastoris: inhibition of pro-inflammatory cytokines (TNF-α, IL-6), reduction of nitric oxide and PGE2 in LPS-stimulated immune cells, and antimicrobial peptide activity. These effects are preclinical and involve innate immune pathway modulation.

• shiitake mushroomScientific

  Shiitake mushroom (Lentinula edodes) has human clinical evidence supporting immune modulation, primarily through its beta-glucan lentinan. A 2015 randomized dietary intervention in 52 healthy adults showed that daily shiitake consumption significantly increased gamma delta T-cell and NK-T cell proliferation, raised secretory IgA, and lowered C-reactive protein. Lentinan has also been approved in Japan as an adjunct oncology therapy, and Phase I/II placebo-controlled trials demonstrate its immunomodulatory activity in HIV-positive patients.

• sichuan pepperScientific

  Z. bungeanum polyphenols and alkaloids modulate immune pathways including TLR4/NF-κB/MAPK, suppress pro-inflammatory cytokine production, and have demonstrated antiviral activity against human coronavirus OC43 and anti-HBV activity in vitro. Preclinical evidence is extensive.

• siler rootScientific

  SD root polysaccharides have been shown to modulate macrophage and lymphocyte activity in preclinical models, including activation of RAW 264.7 macrophages and immunocompromised zebrafish immune cells. SD's chromone and coumarin constituents additionally suppress IgE-mediated mast cell degranulation and regulate Th1/Th2 cytokine balance. The 2020 Yang et al. review identifies immunoregulatory activity as a primary pharmacological property.

• silk treeScientific

  A. julibrissin constituents, particularly triterpenoid saponins, demonstrate immunomodulatory activity in preclinical studies. The plant's saponins are used as vaccine adjuvants, and extracts have been found to modulate immune cell activity.

• silymarinScientific

  Silymarin modulates immune function through NF-κB suppression, reduction of TNF-α, IL-1α, IL-6, and inhibition of T-lymphocyte activation. Clinical studies show it increases superoxide dismutase activity in lymphocytes and erythrocytes. These immunomodulatory effects underlie its anti-inflammatory activity across hepatic, cutaneous, and systemic conditions.

• skullcapScientific

  S. baicalensis has well-documented immunomodulatory effects: it regulates Th1/Th2 balance, suppresses IgE production, inhibits mast cell histamine release, and modulates NF-κB-driven innate immunity. These effects have been demonstrated in multiple preclinical studies and support traditional use for allergic and inflammatory immune conditions.

• smilaxScientific

  Smilax extracts and isolated compounds demonstrate immunomodulatory activity in both stimulatory and regulatory directions. Smilaxin (a novel protein from S. glabra) shows immunostimulatory activity; astilbin modulates Th17/Treg balance and was patented for treating autoimmune and inflammatory conditions. The immune modulation is selective rather than globally suppressive.

• solomon's sealScientific

  Polygonatum polysaccharides demonstrate immunomodulatory activity in vitro and in animal models, including enhancement of Natural Killer cell activity and gut-associated lymphoid tissue support. The Chinese Pharmacopoeia and multiple peer-reviewed reviews identify immune regulation as a principal pharmacological action.

• sophoraScientific

  Oxymatrine and matrine from S. flavescens have documented immunomodulatory effects including regulation of dendritic cells, T-cell activity, and cytokine production. Polysaccharides from S. japonica may stimulate white blood cell production. These immunological mechanisms underlie the herb's antiviral and anti-inflammatory applications.

• soursopScientific

  A. muricata extracts exhibit immunomodulatory, antiviral, and antibacterial activity in vitro and in vivo, supporting immune function through multiple mechanisms including modulation of pro-inflammatory cytokines and antiviral phytochemicals.

• soyScientific

  Soy isoflavones modulate immune function through NF-κB inhibition, reduction of pro-inflammatory cytokines (TNF-α, IL-6), and antioxidant mechanisms. Clinical RCTs in metabolic syndrome and CKD show reduced CRP and inflammatory markers. Isoflavones may also modulate innate and adaptive immune responses via ERβ on immune cells.

• spearmint leafScientific

  Spearmint's rosmarinic acid and flavonoids modulate immune function through antioxidant, anti-inflammatory, antibacterial, and immunosuppressant mechanisms documented in preclinical studies. Rosmarinic acid has demonstrated immunosuppressant activity specifically, inducing apoptosis of activated T cells from rheumatoid arthritis patients.

• sphaeranthus indicusScientific

  Immunomodulatory activity is among the scientifically evidenced properties of S. indicus, supported by multiple preclinical studies demonstrating enhanced phagocytic activity, antibody titer stimulation, and sesquiterpene glycoside-mediated immune stimulation.

• spinachScientific

  Spinach provides vitamin C, folate, iron, and antioxidant carotenoids that are essential for immune cell proliferation, differentiation, and function. Its anti-inflammatory phytochemicals modulate NF-κB and cytokine pathways. Folate deficiency impairs lymphocyte division; spinach's folate content directly supports immune competence.

• spirulinaScientific

  Spirulina (Arthrospira platensis) has documented immunomodulatory effects supported by multiple human clinical trials and systematic reviews. Its primary bioactive compound, C-phycocyanin, inhibits pro-inflammatory cytokines and modulates both innate and adaptive immune responses. Clinical evidence includes enhanced natural killer (NK) cell activity, reduced inflammatory markers (CRP, IL-6), and improved immune outcomes in vulnerable populations. Overall evidence is promising but limited by small trial sizes and heterogeneity across studies.

• SPMs (specialized pro-resolving mediators)Scientific

  SPMs are produced by and act on virtually every cell type in both innate and adaptive immunity. They regulate macrophage polarization, neutrophil apoptosis, T cell subset differentiation, and B cell antibody production—all without immunosuppression. SPMs are produced in human lymph nodes, spleen, and blood upon immune cell activation.

• spruceScientific

  Norway spruce inner bark and bark extracts have demonstrated immunomodulatory properties in vitro, attributed to polyphenolic stilbenes, lignans, and galactoglucomannan. Spruce bark resin components suppress pro-inflammatory cytokines while the polysaccharide fraction (GGM) enhances immune signaling. Spruce needle vitamin C content supports immune function traditionally.

• squaleneScientific

  Squalene-based emulsion adjuvants (MF59, AS03) are licensed for use in approved human influenza vaccines, directly demonstrating squalene's capacity to enhance innate and adaptive immune responses. In cell models, squalene modulates macrophage, monocyte, and neutrophil function, shifting pro-inflammatory M1 macrophages toward anti-inflammatory, tissue-repair states.

• st. john's wortScientific

  SJW constituents demonstrate documented antimicrobial, antiviral, and anti-inflammatory immunomodulatory effects. Hyperforin inhibits key inflammatory enzymes (mPGES-1, JAK1, NF-κB), and hypericin shows broad antiviral activity against multiple enveloped viruses in vitro and in vivo.

• stigmasterolScientific

  Stigmasterol modulates both innate and adaptive immune responses: it stimulates non-specific immune responses in vivo, reduces pro-inflammatory cytokine production by macrophages, and restores Treg/Th17 balance in colitis models. Immunomodulatory activity is one of its recognized pharmacological properties.

• strawberryScientific

  Strawberries provide vitamin C—the best-known micronutrient for immune function—at approximately 60 mg per 100 g, meeting the adult RDA in a single serving. Strawberry polyphenols modulate cytokine signaling (reducing IL-6, IL-1β, TNF-α, IL-8) and reduce oxidative stress that impairs immune cell function. Clinical studies confirm reduced circulating inflammatory cytokines with regular strawberry intake.

• streptococcus thermophilusScientific

  S. thermophilus modulates both innate and adaptive immune gene expression in human immune cells. Multiple human cell-based studies and clinical trials show it reduces pro-inflammatory cytokines (IL-18, IL-6, TNF-α) and upregulates anti-inflammatory mediators (IL-10, TGF-β). Clinical evidence is strongest through its role in VSL#3 for inflammatory bowel conditions.

• succinic acidScientific

  Succinate functions as an immunometabolic signal, activating SUCNR1 on macrophages, dendritic cells, and T cells to modulate innate immune responses. Accumulation in inflammatory macrophages drives HIF-1α stabilization and IL-1β production. Succinate also mediates type 2 immune activation via tuft cell detection in the intestine.

• sulforaphaneScientific

  Sulforaphane modulates the immune system by inducing Nrf2-driven antioxidant defense in immune cells, suppressing NF-κB-driven cytokine production, and shifting Th1/Th17 balance. It has been studied in autoimmune conditions and reduces leukocyte oxidative stress in human trials.

• sumaScientific

  P. paniculata extract increased macrophage spreading index and phagocytic activity in mice at 500 mg/kg in a published study. Multiple other studies document immunomodulatory effects including cytokine regulation and NF-κB suppression. Suma is classified as an immunomodulating adaptogen in Brazilian folk medicine.

• sunflowerScientific

  Sunflower seeds provide vitamin E, which supports immune function; vitamin E deficiency is associated with impaired immune responses. Sunflower seed oil applied to preterm neonates significantly reduced nosocomial infection rates in RCTs, demonstrating a clinically meaningful immune-supporting skin barrier effect. Antioxidant phenolics in sunflower also modulate inflammatory immune pathways.

• sunflower oilScientific

  Sunflower oil's vitamin E content supports immune function—vitamin E is an essential nutrient for immune cell maintenance and T-cell function. Topically, sunflower oil's barrier-strengthening properties reduce infection risk in neonates, shown in a 2008 RCT. Linoleic acid modulates inflammatory immune responses via PPAR-α and eicosanoid pathways.

• sweet flagScientific

  A. calamus demonstrates immunomodulatory activity in preclinical studies, including effects on chronic stress-induced immunosuppression and listed 'immunomodulatory' among its validated pharmacological activities in peer-reviewed reviews. The 2020 J. Clin. Med. review cites immunomodulatory effects.

• sweet wormwoodScientific

  Artemisinin and its derivatives demonstrably modulate immune function, with effects on T-cell subsets (Th17/Treg balance), macrophage polarization (M1/M2), NK cell activity, and cytokine profiles. Clinical evidence comes from autoimmune disease trials and allergen immunotherapy studies.

• swertiaScientific

  Swertia chirayita modulates the immune system through anti-inflammatory cytokine suppression, antiviral activity, antimicrobial effects, and antifungal properties. Its compounds regulate TNF-α, IL-1β, IL-6, and NF-κB signaling. Antimalarial and anti-leishmanial activities further demonstrate immune-relevant antiparasitic actions.

• tartarian asterScientific

  Aster tataricus exerts multiple documented immunomodulatory effects. The cyclopeptide astin C inhibits the cGAS-STING innate immune pathway. A water extract study showed stimulation of immune cell cytokine secretion via MAPK signaling. ATE also displays broad-spectrum antiviral activity in mouse models by activating innate interferon signaling, reducing viral loads and mortality.

• taurineScientific

  Taurine is present in high concentrations in leukocytes, where its metabolite taurine-chloramine (TauCl) and taurine-bromamine (TauBr) modulate immune function by inhibiting NF-κB-dependent cytokine production while also providing antimicrobial activity.

• teaselScientific

  Dipsacus asper root contains saponins, iridoids, and polyphenols with documented immunomodulatory properties in preclinical studies. The 2020 comprehensive review confirms immunological bioactivities. Traditional herbalism also credits teasel with supporting immune responses, particularly in the context of chronic infections.

• terminaliaScientific

  T. chebula has documented immunomodulatory activity. Alcoholic extract of T. chebula ripe fruits was studied for immunomodulatory effects. T. arjuna attenuated immune imbalance in stable coronary artery disease patients in a clinical study. T. chebula additionally shows broad-spectrum antimicrobial, antiviral, and antifungal activity supporting immune defense.

• tetrahydro iso-alpha acidsScientific

  THIAA modulates key immune signaling hubs including NF-κB, AP-1, and multiple protein kinases (BTK, Syk, PI3K isoforms, PKCβII) involved in innate and adaptive immune responses. It reduces LPS-stimulated TNF-α, IL-6, and PGE2 in macrophages and ex vivo in human PBMCs. These effects position THIAA as a broad immunomodulatory agent acting on shared inflammatory cascades.

• thymeScientific

  Thyme modulates immune function through multiple documented mechanisms: thymol and carvacrol have direct antimicrobial activity reducing infectious burden; rosmarinic acid modulates complement and cytokine activity; and thyme/ivy and thyme/primula clinical preparations are validated in RCTs for respiratory immune support. The WHO and German Commission E recognize thyme for immune-relevant infectious conditions.

• thymoquinoneScientific

  Thymoquinone (TQ), the principal bioactive constituent of Nigella sativa (black seed) oil, exerts well-documented immunomodulatory and anti-inflammatory effects supported by extensive preclinical evidence and a limited but growing body of human/clinical data. Its mechanisms include suppression of NF-κB signaling, downregulation of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6), and inhibition of COX-2 and 5-lipoxygenase pathways. Human clinical trials remain limited in number, but include randomized controlled studies showing reductions in systemic inflammatory markers such as TNF-α and C-reactive protein.

• thymusScientific

  Thymus vulgaris and its active constituents exhibit immunomodulatory activity, modulating cytokine profiles, upregulating antioxidant defences, and influencing innate immune cell function in multiple in vitro and animal studies. Thyme preparations are recognised as immunomodulatory agents in pharmacological literature. Clinical immunomodulatory evidence arises indirectly from respiratory infection trial data.

• tinospora cordifoliaScientific

  Tinospora cordifolia (Guduchi/Giloy) has documented immunomodulatory activity supported by in vitro, animal, and limited human clinical studies. Seven distinct bioactive compounds have been isolated that stimulate phagocytosis and modulate cytokine production. A randomized double-blind placebo-controlled trial in HIV-positive patients found symptomatic improvement in 60% of the TCE group vs. 20% on placebo, though not all hematological endpoints were significant. NIH/LiverTox notes that robust human evidence confirming the immunological effects seen in animal studies remains limited.

• tocotrienolsScientific

  Tocotrienols modulate immune function through NF-κB suppression, downregulation of pro-inflammatory cytokines, and antioxidant protection of immune cells. Clinical studies in CKD, NAFLD, and T2DM populations show significant reductions in immune-inflammatory markers including CRP, IL-6, and TNF-α.

• tomatoScientific

  Tomato consumption has been shown in clinical trials to increase resistance of mononuclear leukocytes against DNA strand breaks from reactive oxygen species. Lycopene modulates immune-relevant signaling (NF-κB, Nrf2) and reduces markers of immune-driven inflammation (IL-6, ICAM-1) in intervention trials.

• tongkat aliScientific

  A randomized, double-blind, placebo-controlled 4-week RCT in 81 middle-aged Japanese adults (200 mg/day LJ100) found significant increases in total T-cells, naïve T-cells, and CD4+ T-cells, and a significant improvement in overall immunological vigor versus placebo. Immunological age was approximately 4 years younger in the TA group. This constitutes the first clinical evidence of immune-stimulatory effects from Tongkat Ali.

• trans-pterostilbeneScientific

  Pterostilbene modulates immune function through NF-κB inhibition (reducing pro-inflammatory cytokine production), Nrf2 activation (antioxidant defense), and direct antifungal activity against Candida species. It has also demonstrated anti-edematous and anti-inflammatory cell-infiltration effects in vivo.

• tributyrinScientific

  Tributyrin modulates intestinal and systemic immune function by promoting regulatory T cell (Treg) differentiation, reducing pro-inflammatory cytokines (TNF-α, IL-1β), and increasing IL-10. Animal studies demonstrate preservation of intestinal innate immune responses and reduction of oxidative stress during inflammatory challenge.

• trichosanthesScientific

  Trichosanthin (TCS) from T. kirilowii is a well-characterized immunomodulatory protein with documented anti-HIV, immunostimulatory, and immunosuppressive activities depending on context. It modulates T-helper cell balance, increases IFN-γ-producing CD4+ and CD8+ T cells in tumor models, and enhances chemokine receptor signaling in leukocytes. TK polysaccharides also demonstrate immunomodulatory activity on macrophages.

• triphalaScientific

  Triphala's immunomodulatory activity is documented in preclinical and early human studies. It suppresses excessive inflammatory cytokines (TNFα, IL-1β, IL-6), modulates macrophage function, prevents immunosenescence, and enhances cell-mediated immune responses. These effects are attributed primarily to gallic acid and polyphenolic constituents.

• trypsinScientific

  Trypsin activates protease-activated receptor 2 (PAR2), a key modulator of inflammatory and immunological reactions. Clinical studies demonstrate oral proteolytic enzyme preparations produce immunomodulatory effects in healthy volunteers. Preclinical evidence also indicates proteolytic enzyme preparations have immunomodulatory properties related to degradation of aberrant immune complexes.

• turkey tail mushroomScientific

  Turkey Tail mushroom (Trametes versicolor) has well-documented, clinically studied immunomodulatory effects, primarily attributed to its two key proteoglycan fractions, PSK (polysaccharide-K/Krestin) and PSP (polysaccharide-peptide). Human clinical trials have demonstrated that these compounds stimulate innate and adaptive immune responses, including enhanced NK cell activity, increased lymphocyte counts, and upregulation of CD8+ T cells and CD19+ B cells. PSK has been an approved adjuvant cancer immunotherapy in Japan since the 1970s, with multiple randomized controlled trials supporting improved immune function and survival outcomes when combined with conventional cancer treatment.

• turmericScientific

  Curcumin is well-established as an immunomodulator, interacting with mast cells, eosinophils, T cells, dendritic cells, and macrophages via NF-κB, COX-2, and cytokine regulation. Clinical and preclinical evidence supports its ability to modulate both innate and adaptive immunity. It has been studied in autoimmune, allergic, and infectious inflammatory contexts.

• tylophoraScientific

  Tylophora alkaloids have been shown in multiple peer-reviewed experimental studies to modulate cellular immunity, suppressing delayed-type hypersensitivity, T-cell proliferation, and IL-2 production, while inhibiting mast-cell activation and anaphylactic responses. These immunomodulatory effects are documented in recognized phytomedicine journals and represent the most scientifically characterized pharmacological property of Tylophora beyond its respiratory uses.

• urolithin aScientific

  A 2025 randomized placebo-controlled trial in healthy middle-aged adults found 28 days of UA shifted CD8+ T cells toward a less exhausted phenotype, expanded beneficial NK cell subsets, enhanced monocyte bacterial clearance, and reprogrammed immune cell metabolism toward mitochondrial oxidation. These changes reflect improved immune fitness with aging.

• vanillaScientific

  Vanillin modulates immune function through suppression of pro-inflammatory cytokines and microglial/macrophage activation. Multiple preclinical studies show it inhibits NF-κB and MAPK signaling, reducing TNF-α, IL-1β, and IL-6 across immune cell types including macrophages, microglia, and fibroblasts. Antibacterial properties against multidrug-resistant pathogens add further immune-relevant activity.

• vitamin AScientific

  Vitamin A is essential to the development and regulation of the immune system, with its deficiency constituting a nutritionally acquired immunodeficiency disorder. It supports epithelial and mucosal barrier integrity, T- and B-cell function, innate immune cell activity, and antibody production. Multiple randomized controlled trials and a large Cochrane-style meta-analysis (47 RCTs, ~1.2 million children) confirm that supplementation reduces all-cause mortality, diarrhoea incidence, and measles morbidity in deficient populations.

• vitamin B1Scientific

  Thiamine is an important cofactor for immune cell function, regulating T cells, B cells, and natural killer cells. It also has anti-inflammatory effects, reduces production of pro-inflammatory cytokines, and protects immune cells from oxidative damage through glutathione upregulation.

• vitamin B2Scientific

  Riboflavin supports immune function through its role in optimizing reactive oxygen species (ROS) in the antimicrobial response and through anti-inflammatory mechanisms. It inhibits NF-κB signaling, reduces pro-inflammatory cytokines (TNF-α, IL-1β, COX-2), and elevates the anti-inflammatory cytokine IL-10. The NIH StatPearls monograph explicitly states riboflavin supports immune health.

• vitamin B5Scientific

  Pantothenic acid is required for antibody synthesis and plays a role in immune cell energy metabolism via CoA. B5 deficiency is associated with a pro-inflammatory immune state. The Phytother Res review (2020) identifies B5 deficiency as producing proinflammatory cytokine dysregulation, and CoA is essential for T-cell metabolic programming.

• vitamin B6Scientific

  PLP is essential for lymphocyte proliferation and trafficking; B6 deficiency is established to cause lymphopenia and immunosuppression. Clinical studies in critically ill and dialysis patients show supplementation increases lymphocyte counts and T-cell subpopulations, and in vitro work shows high-dose B6 broadly downregulates pro-inflammatory cytokines.

• vitamin CScientific

  Vitamin C plays a well-documented, mechanistically defined role in supporting immune function, backed by substantial clinical and experimental evidence. It accumulates in leukocytes, supports phagocytosis, chemotaxis, and antioxidant defense, and is rapidly consumed during infection. Cochrane-level evidence shows regular supplementation modestly reduces cold duration, though it does not prevent colds in the general population. Evidence for high-dose therapeutic use in severe infections remains inconclusive.

• vitamin DScientific

  Vitamin D is well-established as an immunomodulatory nutrient with substantial clinical and mechanistic evidence. Immune cells—including dendritic cells, macrophages, and T and B cells—express both the vitamin D receptor (VDR) and the enzyme needed to convert vitamin D to its active form, directly linking it to immune regulation. Epidemiological and clinical studies consistently associate low vitamin D status with greater susceptibility to infections and autoimmune disorders. Multiple meta-analyses of RCTs show a modest but significant protective effect of supplementation against acute respiratory infections, particularly with daily low-dose regimens in deficient individuals.

• vitamin EScientific

  Vitamin E is a fat-soluble antioxidant with well-documented immunomodulatory activity supported by both mechanistic and clinical evidence. It maintains immune cell membrane integrity, enhances T cell-mediated function, and supports antibody production and natural killer cell activity. The evidence is strongest for older adults, where supplementation above the RDA has been shown in randomized controlled trials to improve cell-mediated immunity and reduce infection risk.

• wasabiScientific

  Wasabi/6-MSITC modulates immune function by inhibiting NF-κB and AP-1 pathways, reducing pro-inflammatory cytokines (IL-6, TNF-α, iNOS, COX-2), and suppressing macrophage over-activation. Simultaneously, antimicrobial activity against multiple pathogens supports innate immune defense. These mechanisms are well-characterized in vitro and in animal models.

• watercressScientific

  A controlled human study in 19 healthy adults found watercress consumption before exercise led to a stronger anti-inflammatory downregulation of pro-inflammatory cytokines (IL-6, TNF-α) during recovery compared to control. Human RCTs also show watercress raises plasma antioxidants (carotenoids) that support immune cell integrity, and the Gill 2007 RCT demonstrated reduced DNA damage to lymphocytes.

• watermelonScientific

  Watermelon provides vitamin C, vitamin A, and lycopene, all of which support immune function. Vitamin C supports immune cell activity and vitamin B6 in watermelon is important for lymphocyte production. Lycopene's anti-inflammatory activity reduces chronic immune activation that impairs immunity.

• wheatScientific

  Wheat bran AX and polyphenols modulate immune function through gut microbiota-mediated and direct mechanisms. Wheat-derived arabinoxylan increased colonic regulatory T cells (Tregs) in animal studies, potentially dampening mucosal over-reactivity. SCFA produced from wheat fiber fermentation have documented immunomodulatory effects in humans, including anti-inflammatory cytokine profiles.

• wheat germScientific

  Wheat germ contains zinc, selenium, vitamin E, and protein hydrolysates that support immune function. Zinc and selenium are established immunomodulatory micronutrients. Wheat germ protein hydrolysates have been shown to stimulate antioxidant activity within the immune system. Fermented wheat germ extract has been investigated in autoimmune and inflammatory conditions in clinical studies.

• wheat grassScientific

  A 2013 PMC study identified a specific wheatgrass-derived oligosaccharide (maltoheptaose) that activates human monocytes via Toll-like receptor-2 signaling, providing a defined molecular mechanism for immune stimulation. A human trial in cancer patients showed higher anti-inflammatory IL-10 and attenuated WBC decline during chemotherapy in the wheatgrass group.

• whey proteinScientific

  Whey protein contains multiple immunomodulatory bioactives—lactoferrin, alpha-lactalbumin, immunoglobulins, GMP, and cysteine—that collectively enhance innate and adaptive immune responses. Whey supplementation has been shown to modulate immune cell activity, support antibody production, reduce pro-inflammatory cytokines (especially in older adults), and boost glutathione-mediated antioxidant defense.

• willowScientific

  Willow bark extract modulates key immune mediators: it inhibits TNF-α and IL-6 production in activated human monocytes and macrophages, blocks NF-κB nuclear translocation, and activates the Nrf2 antioxidant pathway. These effects represent direct modulation of innate immune inflammatory signaling. Its antipyretic action—mediated by COX-inhibitory suppression of prostaglandin E2 at the hypothalamic level—also represents immune-temperature regulatory activity recognized formally by the EMA.

• xanthium (cockleburs)Scientific

  X. strumarium extracts modulate immune responses through suppression of NF-κB, MAPK, STAT3, and JAK-IKK signaling—key immune regulatory pathways. Its anti-allergic effects involve inhibiting mast cell degranulation, Th2 polarization, and IgE production. Immunomodulatory activity is among its best-characterized pharmacological properties.

• xylanaseScientific

  XOS generated by xylanase fermentation in the colon drives SCFA production, particularly butyrate and propionate, which regulate innate and adaptive immune responses. Research documents XOS immunomodulatory effects including modulation of pro- and anti-inflammatory cytokine secretion. Animal models show XOS reduces plasma TNF-α and LPS levels and supports intestinal immune barrier integrity. The immune link is mediated via the gut-microbiome-immune axis rather than direct xylanase action.

• xylooligosaccharidesScientific

  XOS modulates immune function by enriching beneficial gut bacteria that interact with intestinal immune cells, increasing secretory IgA, and regulating cytokine production. Multiple studies show XOS promotes immune balance via microbiota-mediated pathways. Both human and animal data support its immunomodulatory role.

• yarrowScientific

  Yarrow demonstrates immune-modulating activity including antimicrobial, anti-inflammatory, immunological, and antiplatelet properties. It inhibits pro-inflammatory cytokines and LPS-induced macrophage activation while supporting innate immune functions against bacterial pathogens.

• yeastScientific

  Beta-1,3/1,6-D-glucan from S. cerevisiae cell walls has demonstrated immunomodulatory effects in multiple human clinical trials, enhancing macrophage phagocytic activity, natural killer cell function, and reducing upper respiratory tract infection duration and severity. Several human studies confirm that oral yeast beta-glucan has immune-strengthening effects.

• yerba mateScientific

  Yerba mate contains saponins and polyphenols with immunomodulatory properties. A 2025 RCT showed significant reductions in inflammatory cytokines and chemokines. In vitro studies demonstrate antimicrobial activity and modulation of macrophage inflammatory responses.

• yuccaScientific

  Yucca saponins and phenolics modulate immune function through NFκB inhibition, reduction of pro-inflammatory cytokines, and antioxidant protection of immune cells. Animal studies show immunostimulatory effects including enhanced spleen and lymph node indices with yucca extract. Saponins also have anti-protozoal activity, contributing to immune defense against parasitic challenge.

• zanthoxylumScientific

  Zanthoxylum modulates immune function through demonstrated effects on pro- and anti-inflammatory cytokines, NF-κB/MAPK signaling, and antimicrobial activity against bacteria, fungi, and parasites. The broad antimicrobial and anti-inflammatory pharmacology collectively supports immunological relevance. All evidence is preclinical.

• zeoliteScientific

  A prospective, controlled, parallel-group clinical study in 61 immunodeficient patients found that TMAZ clinoptilolite supplementation improved cellular immune parameters (blood and lymphocyte counts) over 6–8 weeks. Mechanistic research shows clinoptilolite interacts with intestinal M-cells and Peyer's patches, modulating immunological signaling. Animal studies broadly document immunostimulatory and immunomodulatory effects.

• zincScientific

  Zinc is an essential trace element with well-established, clinically documented roles in both innate and adaptive immune function. Deficiency impairs the development and activity of neutrophils, NK cells, T cells, and B cells, and raises inflammatory cytokine tone. Multiple RCTs and meta-analyses confirm that zinc supplementation modulates immune biomarkers and, in certain formulations and doses, reduces duration of upper respiratory infections.

• adrenal cortexTraditional

  The adrenal cortex is the source of cortisol, the body's primary endogenous immunomodulator, making adrenal cortex function intrinsically linked to immune regulation. Adrenal cortex supplements are marketed for immune support on this basis. No clinical trial has demonstrated that OTC adrenal cortex supplements measurably alter immune function in humans.

• argan nut oilTraditional

  Argan oil modulates immune-inflammatory signalling via NF-κB inhibition and IL-10/anti-inflammatory pathway activation in preclinical models. Human data on immune function per se are lacking, but anti-inflammatory effects in cardiovascular trials provide indirect human evidence.

• bacopaTraditional

  Bacopa modulates innate immune function through suppression of pro-inflammatory cytokines in macrophages and human blood cells. In vitro work using human blood cells showed down-regulation of TNF-α, IFN-γ, and nitric oxide, with elevation of anti-inflammatory IL-10. Research highlights Bacopa's potential to boost immune function, but no in vivo human immunology RCTs exist.

• bayberryTraditional

  Bayberry has been used in multiple herbal traditions as an immune-supportive herb, particularly for cold, flu, and infection prevention. Its antimicrobial (myricitrin) and anti-inflammatory (flavonoids, tannins) constituents are proposed to support immune function. TCM records over 2,000 years of such use.

• blessed thistleTraditional

  Blessed thistle is traditionally used for immune support, with in vitro evidence that cnicin and the essential oil possess antimicrobial and antiviral properties. In vitro studies show activity against bacteria (S. aureus, E. coli, Salmonella) and viruses. Traditional use as an antimicrobial and anti-infective spans centuries. No human clinical trials confirm immune-modulatory effects.

• bovine heartTraditional

  Traditional and ancestral dietary practices consistently featured organ meats, including heart, as foods for systemic vitality, general robustness, and resistance to illness. Bovine heart provides selenium and zinc, micronutrients with established immune roles, but no clinical evidence exists specifically linking bovine heart supplementation to immune function outcomes.

• bovine spleenTraditional

  Bovine spleen contains tuftsin and splenopentin, peptides with documented immunomodulatory activity in preclinical research. Historically, spleen extracts were used to raise white blood cell counts and improve resistance to infection. No robust human RCTs confirm these effects when bovine spleen is taken orally as a supplement.

• cassia barkTraditional

  Cassia bark's antimicrobial, antifungal, and anti-inflammatory properties provide a pharmacological basis for immune support, and it is listed as an immune system herb in multiple TCM and traditional medicine monographs. One clinical study examined C. cassia against Helicobacter pylori with no significant effect. Overall immune system evidence is traditional with supporting in vitro/preclinical science.

• cellulaseTraditional

  Cellulase, as part of multi-enzyme formulas, has been associated with improved immune markers in at least one small clinical study in nursing home patients. Dietary cellulose also modulates murine immune responses in endotoxemia models. The connection is indirect—mediated through improved digestion, SCFA production, and gut microbiome support—rather than a direct immunostimulatory effect of cellulase itself.

• chlorophyllTraditional

  Chlorophyllin has been attributed immune-supporting properties based on preclinical evidence showing immunostimulatory effects, potential enhancement of white blood cell production, and anti-inflammatory modulation. Traditional and naturopathic frameworks position chlorophyll as an immune tonic. Direct human clinical evidence for immune-specific outcomes (e.g., infection resistance, immune cell counts) is absent.

• fennelTraditional

  Fennel's antimicrobial and anti-inflammatory properties, documented in vitro and in animal studies, suggest immune-supportive potential. The antioxidant polyphenols may reduce oxidative burden on immune cells. Traditional use includes fennel as a general tonic; direct human immune outcome studies are lacking.

• gentianTraditional

  Gentian has been used in traditional European herbal medicine as a cooling bitter for infectious diseases and fever. Herbal Reality documents its traditional use in infectious disease management and post-fever recuperation. A human cell study (Herbal Reality) showed gentian extract protected peripheral blood mononuclear cells from radiation damage. Anti-inflammatory effects may indirectly modulate immune activity. No clinical immune trials have been conducted.

• goldenrodTraditional

  Goldenrod exhibits immunomodulatory properties documented in pharmacological studies, including effects on immune cell activity characterized in non-clinical research. Traditional use positions it as a supportive herb during upper respiratory infections and urinary tract infections. Immunomodulatory action is listed in the PMC systematic review of S. virgaurea pharmacology.

• greek mountain teaTraditional

  The EMA Assessment Report (2016) specifically cites GMT's traditional use to 'strengthen the immune system.' GMT contains immunomodulatory polyphenols documented in peer-reviewed research. Antimicrobial and antiviral activities have been confirmed in vitro. Clinical evidence for immune system modulation in humans is not yet established.

• huckleberryTraditional

  Huckleberry was traditionally valued as an immune tonic due to its high vitamin C content and general antioxidant profile. Folk medicine used huckleberry preparations for colds, fevers, and infections. Vitamin C's role in immune function is well-established scientifically, supporting the plausibility of this traditional use.

• indian gum arabic treeTraditional

  Acacia nilotica has traditional use for immune-related conditions including infections, smallpox, and malaria. The antibacterial, antifungal, antiviral, and anti-inflammatory properties provide immunological rationale. Clinical data on inflammatory markers (CRP, TNF-α) provide indirect immune-modulating evidence.

• lemon balmTraditional

  Lemon balm has traditionally been used as an antimicrobial and antiviral herb. Pharmacological evidence documents antimicrobial, antiviral (against herpes simplex), and anti-inflammatory properties. Rosmarinic acid modulates inflammatory cytokines. Clinical trial evidence for direct immune enhancement is limited, with the best clinical data existing for topical antiviral (herpes) use.

• lemongrassTraditional

  Lemongrass is documented in folk medicine as an immune-supportive herb through its antimicrobial, antipyretic, and anti-inflammatory actions. Preclinical evidence shows antimicrobial activity against a range of pathogens. Traditional use across multiple systems involves lemongrass for infectious conditions. Formal immune-modulation human trials are absent.

• mulberryTraditional

  Mulberry leaf is documented in TCM for supporting the body's defensive Qi (Wei Qi) against external pathogens, particularly in Wind-Heat infections. In vitro, mulberry leaf decoctions inhibit multiple pathogenic bacteria. Clinical evidence for immune-modulating effects is not directly established.

• papainTraditional

  Papain has been proposed to modulate immune function through proteolytic degradation of immune complexes, immunoglobulins, and pro-inflammatory proteins. Papain is described in traditional medicine as an immunity-supporting compound, and fresh papaya juice is marketed as an immunity booster. Scientific evidence for direct immunomodulatory effects in humans is limited and largely mechanistic or observational.

• prickly ashTraditional

  Prickly ash is classified as an immunomodulator and alterative in professional herbal monographs. It is described as enhancing 'the body's ability to fight against and recover from all manner of difficulties.' The antimicrobial activity of chelerythrine against MRSA and the antifungal furanocoumarins provide a preclinical basis for immune-supportive properties.

• red cloverTraditional

  Red clover has a traditional role in immune system support through its 'alterative' and 'blood-purifying' classification in European, Asian, and Ayurvedic medicine. Flavonoids and isoflavones have demonstrated immunomodulatory activity in vitro. Traditional use included treatment of infections and immune-related skin conditions. No clinical trial evidence for direct immune outcomes exists.

• red rootTraditional

  Red root has been used by Native Americans and Eclectic herbalists to support immune defense during infections, particularly through its action on the lymph and spleen. Herbalists describe it as promoting lymphocyte production and supporting recovery from chronic or acute infections. No controlled human immunological trials have been conducted specifically on Ceanothus americanus.

• rosa californicaTraditional

  Rosa californica hips were historically valued by California tribes and WWII-era foragers for their high vitamin content as a support for general health and immunity. The vitamin C and polyphenol content of wild rose hips is recognized as supportive of immune function, though clinical evidence is from related species only.

• sheep's sorrelTraditional

  Sheep's sorrel's high vitamin C content and antioxidant compounds have supported its traditional use as an immune-supporting herb, including its anti-scorbutic (anti-scurvy) properties. Genus-level antiviral activity has been shown in vitro. No human immune trials exist for R. acetosella.

• siliconTraditional

  Animal studies suggest silicon may modulate immune and inflammatory responses, with silicon-deprived animals showing altered immune cell profiles. Silicon deficiency has been linked to increased susceptibility to infection, and silicon-supplemented rats with collagen-induced arthritis showed modified lymphocyte and neutrophil counts. No human RCTs have directly tested silicon's effect on immune function outcomes.

• slippery elmTraditional

  Slippery elm is proposed to support immune function indirectly through its prebiotic soluble fiber, which feeds beneficial gut bacteria, and through antioxidant polyphenols that reduce oxidative stress. These are mechanistic and traditional claims; no clinical trials have directly evaluated slippery elm as an immune modulator.

• slippery elm barkTraditional

  Slippery elm's immune relevance is indirect: its prebiotic action supports gut microbiome diversity, which in turn modulates immune function. Traditional references include it in immune-supporting herbal blends. No direct immunomodulation studies in humans have been conducted specifically with slippery elm.

• stillingiaTraditional

  Stillingia was traditionally associated with immune support indirectly through its alterative and lymphatic-stimulating actions. Eclectic physicians used it for scrofula and conditions involving swollen lymph nodes, suggesting recognized immune-modulating effects. No clinical immune studies exist.

• white oakTraditional

  White oak bark has antimicrobial, anti-inflammatory, and antioxidant properties that support immune function in a broad traditional context. Its tannins inhibit bacterial and potential viral activity. Laboratory evidence of immunomodulatory activity exists, but no human clinical trials targeting the immune system directly have been conducted.

• whole adrenal glandularTraditional

  Whole adrenal glandular is traditionally proposed to support immune function on two grounds: that adrenal glucocorticoids modulate immune response, and that the glandular tissue provides immune-supportive nutrients. Both WebMD and RxList list immune support as a traditional use. One theoretical mechanism—that oral adrenal tissue diverts autoantibodies from human adrenal tissue—is cited in traditional literature but lacks scientific plausibility according to EBSCO. No clinical evidence supports this application.

• yellow rootTraditional

  Yellow Root has been documented as an immunostimulant herb in folk medicine and has been used in immune-supportive herbal formulations. Berberine's immunomodulatory properties have been studied, including effects on immune cell function. Traditional use as an antimicrobial and immune tonic is well documented.