Warts (Verrucae): A Nutrition and Natural-Health Reference
Definition and Overview
Warts are benign proliferations of skin and mucosa caused by the human papillomavirus (HPV). The human papillomavirus (HPV) is a non-enveloped, double-stranded, circular DNA virus that is responsible for causing multiple epithelial lesions and cancers. Many HPV infections cause no symptoms and 90% resolve spontaneously within two years; sometimes an HPV infection persists and results in warts or precancerous lesions.
Currently, more than 200 types of HPV have been identified. Certain HPV types tend to infect skin at particular anatomic sites; however, warts of any HPV type may occur at any site. Although the frequency is unknown, warts are estimated to affect approximately 7–12% of the population.
Clinical Presentations and Types
The primary clinical manifestations of HPV infection include common warts, genital warts, flat warts, and deep palmoplantar warts (myrmecia). Less common manifestations of HPV infection include focal epithelial hyperplasia (Heck disease), epidermodysplasia verruciformis, and plantar cysts.
Common wart types and associated HPV types include: common warts — HPV types 2 and 4 (most common), followed by types 1, 3, 27, 29, and 57; deep palmoplantar warts (myrmecia) — HPV type 1 (most common), followed by types 2, 3, 4, 27, 29, and 57. HPV6 and HPV11 are common causes of genital warts and laryngeal papillomatosis. Some high-risk HPV subtypes are associated with malignancies, including types 6, 11, 16, 18, 31, and 35. Malignant transformation is usually seen in patients with genital warts and immunocompromised patients.
Common warts (Verruca vulgaris) are by far the most prevalent type of wart, making up 70% of all non-genital cutaneous warts, and are thought to be benign in nature.
Body Systems Involved
The Integumentary System (Skin and Mucosa)
HPV exclusively targets the lowermost epidermal layer, the stratum basale, in order to establish a persistent infection, after which it hijacks the keratinocyte differentiation process for the purpose of the productive viral life cycle. Keratinocytes make up 90% of all epidermal cells, and perturbations to their differentiation make the skin more susceptible to infection and disease.
At the keratinized layer, the virus is present in high copy numbers and is shed with exfoliated cells. This replication process alters the character of the epidermis, resulting in cutaneous or mucosal excrescences known as warts.
The Immune System
The immune system plays a central role in the natural history of HPV infection and wart formation. Usually, the immune system controls HPV infections, and they go away on their own and don't cause any health problems, but some need treatment. Although most immunocompetent individuals can clear the infection within 12 months, anti-HPV antibodies are only detected 6–12 months after infection.
Reinfection with the same HPV type is uncommon after clearance, suggesting that protective type-specific immunity may develop. Effective immunity depends on cell-mediated immune response to the early proteins, principally E2 and E6, which promotes the regression of the lesion.
Cell Cycle and Oncogenic Mechanisms
E6 and E7 are oncoproteins that inactivate p53 and pRb proteins, respectively; these inactivations lead to dysregulation of the cell cycle and neoplastic transformation of the affected tissue. Low-risk types of HPV, including HPV 6, 11, 42, 43, and 44 are linked to the development of non-cancerous genital warts and other seemingly benign epithelial lesions. The immune system typically clears low-risk HPV infections more rapidly compared to high-risk types.
Contributing and Associated Factors
Immunosuppression
The prevalence and potential for significant morbidity and mortality from HPV may be higher in patients with underlying immunodeficiencies such as Warts, Hypogammaglobulinemia, Infections, Myelokathexis (WHIM) syndrome. Similarly, patients with undiagnosed inherited or acquired immunodeficiencies may demonstrate refractory or more severe HPV infections.
A weakened immune system is a major risk factor. HIV/AIDS or certain medicines used after organ transplants can weaken immune systems. People who have weakened immune systems are at greater risk of HPV infections.
Skin Barrier Disruption
Warts are transmitted by direct or indirect contact, and predisposing factors include disruption to the normal epithelial barrier. Minor damage to the epithelium allows HPV infection of the basal epithelium. Areas of skin that have been injured are more likely to develop common warts.
Age
Common warts occur mostly in children. Genital warts occur most often in adolescents and young adults.
Smoking
Smoking could influence the incidence and persistence of HPV infections by suppressing local immune function, increased cellular proliferation, upregulated proinflammatory factors, or induced host DNA damage resulting in increased susceptibility to infection. The incidence and recurrence rates of anogenital warts are significantly increased in smokers. Most current data demonstrate an association between smoking, increased anogenital HPV infection, and development of anogenital warts. Smoking has been proven to cause a wide range of suppression of immunological functions. In smokers compared with non-smokers, a significant reduction of Langerhans cells in the normal cervical epithelium was observed.
HIV Status and CD4 Count
Factors associated with acquisition and persistence of oral HPV infection include cigarette smoking and immunosuppression. People living with HIV (PLWH) have 2–3 times higher oral HPV prevalence than HIV-uninfected individuals and the risk of both incident oral HPV detection and its persistence in PLWH increases with diminishing CD4 cell count.
Vaginal Microbiota (Dysbiosis)
Additional factors correlated with HPV persistence include immunodeficiency caused by HIV, smoking, use of oral contraceptives, and vaginal dysbiosis. In a state of dysbiosis, there is a marked reduction of Lactobacillus and a high diversity of bacteria, with increased abundance of anaerobic bacterial species.
Overall Lifestyle Metrics
Health behaviors including diet quality, physical activity, smoking, obesity, cholesterol, glucose, and blood pressure can modulate immune function and susceptibility to infectious diseases, with plausible mechanisms relating to changes in mucosal immunity, inflammation, oxidative stress, and micronutrient status. Higher physical activity levels were associated with a reduced risk of HPV infection, likely due to enhanced immune function.
Nutrients Studied in Relation to Warts and HPV
The following section separates traditional use from scientific evidence, with honest characterization of evidence strength. Much of the nutritional research has focused on HPV persistence and associated cervical lesions (CIN) rather than cutaneous warts specifically; this distinction is noted where relevant.
Zinc
Scientific Evidence
Zinc is the most extensively studied micronutrient in relation to cutaneous warts. Zinc is a trace element essential for growth and development at all stages of life, and plays a key role in homeostasis, immune function, oxidative stress, apoptosis, and aging. Zinc is essential for the normal development and function of cell-mediated innate immunity, such as neutrophils, natural killer cells, and macrophages. In recent decades, the role of zinc as an immunological modulator that activates lymphocytes and cytokines against the penetration and replication of viruses has increasingly been recognized.
Zinc deficiency is associated with persistent, progressive, or recurrent viral warts in studied patients. One study found that serum zinc level was low in 42 (56%) patients with warts and 24 (32%) controls (p=0.003). Zinc deficiency negatively affects Th17 cells. IL-6-induced STAT3 activation during chronic inflammation and Th17 development is suppressed by zinc via attenuating this activation, which critically controls Th17-cell development.
In clinical trials: 78% and 100% of patients showed clearance of lesions in response to oral zinc sulfate (10 mg/kg up to 600 mg/d) compared to 13% and 0% of the placebo group, respectively. However, individuals with persistent viral warts are often zinc-deficient or have lower concentrations than their healthy counterparts. Studies demonstrating the most significant responses to zinc treatment had engaged patients that were primarily zinc-deficient (>70 µg/dL). This suggests the benefit may be most pronounced in those with true deficiency.
For topical application: a small study using a 4-week topical 10% zinc sulfate regimen for plane warts demonstrated an 86% response rate (6/7), compared to a 10% response rate (1/10) in the control group.
A 2025 systematic review and meta-analysis confirmed that zinc compounds are efficacious and safe choices for patients with viral warts and cervical HPV infection. The overall evidence for zinc in warts is moderate, derived primarily from randomized controlled trials in zinc-deficient populations and small trials; larger, adequately powered RCTs in zinc-sufficient populations are needed.
Mechanistically, exogenous zinc treatment can effectively inhibit production of viral oncogenic proteins E6 and E7. The inhibition of E6 and E7 by zinc results in apoptosis of cervical carcinoma cells, as they regain the function of tumor suppressors p53 and pRb.
Vitamin D
Scientific Evidence
Vitamin D plays a significant role in the innate immunity of the skin, enhancing the anti-infective effects of macrophages and monocytes by promoting chemotaxis and phagocytosis to boost the functionality of innate immune cells.
A 2024 systematic review of the relationship between serum vitamin D levels and HPV infection found that after careful evaluation of the available studies, the findings showed no clear-cut evidence to suggest vitamin D is associated with HPV, although a few studies claimed this association. One of the most striking observations was the inconsistency in reported findings across various studies. While some studies suggested a potential inverse association between serum vitamin D levels and HPV infection, others failed to establish a significant link.
In a meta-analytic context, however, across 5 studies including 727 women, both oral and vaginal vitamin D supplementation reduced CIN2/3 lesions and improved inflammatory markers (SMD = 0.81 [0.69, 0.93]; p < 0.00001; I² = 0%; GRADE: High). This is relevant to HPV-related lesions rather than common cutaneous warts directly. Warts are an infectious disease complexly influenced by genetic and environmental factors interacting with each other, and this unexpected finding requires further clinical research to confirm the exact role of vitamin D and its metabolites in HPV infection.
Overall, evidence for vitamin D in relation to cutaneous warts specifically is preliminary and indirect. Evidence in the context of cervical HPV lesions is more developed but still mixed.
Folate and Vitamin B12
Scientific Evidence
Nutrients such as folate and vitamins B6 and B12 may have a role in regulating viral integration and gene stability due to their involvement in DNA synthesis, repair, and methylation. Consuming foods that support normal DNA methylation has the potential to suppress expression of viral oncogenes, promote proper signaling pathways, avoid cell transformation, and reduce the risk of cancer in humans.
Folate may slow the evolution of cervical lesions by controlling DNA methylation and gene expression linked to tumor suppression. Vitamin B12 and folate regulate DNA synthesis and repair processes in concert.
A large meta-analysis of 77 studies found that across 4 studies (1,130 women), folate and vitamin B12 showed a protective role in reducing HPV persistence and CIN progression, with favorable effects on DNA methylation and viral clearance (SMD = 0.80 [0.65, 0.95]; p < 0.00001; I² = 0%; GRADE: High).
The observed inverse associations between folate levels and CIN progression align with previous studies. Earlier research has shown that folate deficiency may enhance the carcinogenic potential of HPV through impaired DNA repair mechanisms.
Evidence strength: The GRADE-High rating for folate and B12 in the meta-analysis context is specifically for CIN progression and viral clearance, not for common cutaneous warts. Evidence for non-cervical wart contexts remains limited.
Vitamin E (Tocopherols)
Scientific Evidence
Based on 8 studies involving 2,003 women, a protective vitamin E (particularly α-tocopherol) effect against HPV and cervical neoplasia was noted (SMD = 0.46 [0.36, 0.57]; p < 0.0001; I² = 21.3%; GRADE: Moderate). Studies have consistently reported that antioxidant vitamins such as vitamin C contribute to epithelial cell protection and immune surveillance.
Evidence is moderate (GRADE) and derived from observational and mixed-design studies focused on cervical HPV-related disease; applicability to common warts is indirect.
Vitamin A and Carotenoids
Scientific Evidence
Due to its essential role in the replication of basal and mucosal cells and in the synthesis of protein, vitamin A deficiency could lead to a higher risk of infection and metaplasia. From 6 studies (1,246 individuals), consistent inverse associations between vitamin A intake/status and risk of cervical cancer were observed (SMD = 0.77 [0.68, 0.87]; p < 0.0001; I² = 16.6%; GRADE: Moderate).
The role of vitamin A seems more inconsistent; whereas some research reveals negative relationships between HPV recurrence and the rate of cervical cancer, other investigations reveal no significant correlations. Although retinoid regulation of mucosal immunity and epithelial development provides tenable pathways, population-specific variations in vitamin A levels and food choices may contribute to the cause of varying findings.
A possible protective effect against HPV persistence was noted for fruits, vegetables, vitamins C and E, alpha and beta-carotene, lycopene, lutein/zeaxanthin, and cryptoxanthin. Higher intake of nutrients with antioxidant and antiviral functions may prevent the progression of HPV infection to high-grade cervical intraepithelial neoplasia.
Evidence strength: Moderate (GRADE) for vitamin A. Evidence for carotenoids specifically in wart prevention or resolution is preliminary, based largely on observational data.
Vitamin C
Scientific Evidence
Vitamin C exhibits beneficial connections as well, however there is significant variation among research. Although its function as an immune-enhancing agent and fluid-soluble antioxidant is widely recognized, the lack of RCT information and the variation in nutritional methods of evaluation make the findings less reliable.
Evidence strength: Weak to moderate. No dedicated RCTs for vitamin C in wart resolution have been identified in the peer-reviewed literature; associations derive from observational data on HPV persistence and cervical neoplasia.
Selenium
Scientific Evidence
Selenium supplementation, notably in Iranian trials (GRADE: Moderate), improved oxidative and immune profiles and was associated with CIN2 regression. Nutrients assessed in the broader meta-analysis of 77 studies included vitamins A, C, D, E, K, B-complex, carotenoids, and minerals like selenium, zinc, and calcium; higher dietary intake or serum levels of micronutrients were associated with reduced persistence of HPV and decreased risk of CIN and cervical cancer.
Evidence strength: Moderate for cervical HPV lesions; no direct RCT evidence for selenium in common cutaneous warts.
Herbs and Natural Ingredients: Traditional Use and Scientific Evidence
Sinecatechins (Green Tea Extract / Camellia sinensis)
Traditional Use
Green tea (Camellia sinensis) has been consumed for centuries in East Asian traditions as both a beverage and a medicinal preparation. Its dried leaves and extracts were traditionally used for general health, immune support, and as topical applications for skin conditions across Chinese and Japanese folk medicine, though the specific traditional use of concentrated green tea extracts for warts is a modern pharmacological development rather than a deeply historical folk practice.
Scientific Evidence
Sinecatechins ointment, 15%, is manufactured from the extract of green tea leaves from Camellia sinensis, consisting of 85–95% catechins, with EGCg representing the primary catechin at more than 55%. It is the first botanical agent approved by the United States Food and Drug Administration (FDA) for prescription use and is indicated for use as a topical patient-applied treatment for external genital and perianal warts (EGW).
In a clinical trial in which 502 male and female patients aged ≥18 years received application of sinecatechins ointment 15% or 10% or placebo three times daily for a maximum of 16 weeks or until complete clearance, complete clearance of all baseline and new warts was achieved in 57.2% and 56.3% of patients treated with 15% and 10% ointments, respectively, as compared to 33.7% for placebo. A systematic review and meta-analysis of these clinical trials showed that treatments with Polyphenon E 15% and 10% ointments resulted in significantly higher rates of complete clearance of baseline and new warts when compared with controls, with very low recurrence rates.
In terms of mechanism: results demonstrated that sinecatechins specifically inhibit multiple human papillomavirus-induced pathways and molecules, likely contributing to external genital and perianal wart clearance via direct antiviral activity. Epigallocatechin gallate (EGCG) and Polyphenon E inhibited the growth of HPV-positive cervical cancer cells and HPV-immortalized cervical epithelial cells in a dose-dependent fashion. Induction of apoptosis and cell cycle arrest was observed in EGCG and Polyphenon E treated cells.
For internal/oral use, however, the picture is less positive. A phase II randomized, double-blind, placebo-controlled trial found that in 98 women with persistent high-risk HPV and CIN1, Polyphenon E (containing 800 mg EGCG daily for 4 months) showed no difference in HPV clearance compared to placebo (17.1% vs. 14.6% complete response rate). The results indicated that oral Polyphenon E did not promote the clearance of the virus and intraepithelial neoplasia, suggesting that further studies are required.
Evidence strength: Strong for topical sinecatechins in external genital and perianal warts (FDA-approved; multiple Phase 3 RCTs). Weak to absent for oral EGCG in HPV viral clearance. Laboratory mechanistic data are robust but do not translate consistently to oral clinical outcomes.
Thuja occidentalis (White Cedar / Arborvitae)
Traditional Use
As a tincture, T. occidentalis has been used in the treatment of warts, papillomas, and condylomas caused by human papillomavirus (HPV). Since historical times, the essential oil of T. occidentalis has been used in folk medicine. Thuja preparations with thujone were regularly used by the American Indian traditional healers. The mother tincture of T. occidentalis is used in homeopathy against a number of diseases. Homeopathy uses thuja as one of the main remedies for psychotic constitutions, in case of snake bite, small-pox, and vaccination-induced toxicity, as well as proliferation or pathological vegetation.
Scientific Evidence
The chemical constituents of T. occidentalis have been of research interest for decades, due to their contents of essential oil, coumarins, flavonoids, tannins, and proanthocyanidines. Pharmacology includes antioxidant, anti-inflammatory, antibacterial, antifungal, anticancer, antiviral, protective activity of the gastrointestinal tract, radioprotection, antipyretic, and lipid metabolism regulatory activity. However, clinical trial data specifically evaluating thuja for wart resolution are not robustly available in the peer-reviewed literature. The evidence base for thuja in warts remains largely traditional and pre-clinical.
Evidence strength: Weak. Traditional use is well-documented; in vitro pharmacological data exist; robust human clinical trial evidence for wart resolution is lacking.
Garlic (Allium sativum)
Traditional Use
The deep-rooted presence of garlic in ancient Egyptian, Greek, Chinese, and Indian medicine highlights its cross-cultural medicinal value, much of which modern pharmacology now validates. Traditional systems such as Ayurveda and traditional Chinese medicine recognized its benefits for digestion, immunity, and infection control. In folk traditions across Europe and Asia, raw garlic or garlic juice was applied topically to warts as a local treatment, and garlic was consumed to generally support immune function against infections.
Folk traditions include the use of a 'sandwich technique': wild garlic root is inserted into a hole inside a piece of bacon and attached to the wart using a linen cloth.
Scientific Evidence
The efficacy of garlic is substantiated by its bioactive compounds, allicin, diallyl disulfide, and S-allyl cysteine, which exhibit antimicrobial, antioxidant, and anti-inflammatory properties. Many scientific studies have been published about virustatic and virucidal properties of herbal remedies, but scientific experiments differ considerably from typical traditional medicine and self-healing procedures. Clinical trial evidence specifically for garlic in the treatment of cutaneous warts is very limited and not available through high-quality peer-reviewed sources.
Evidence strength: Weak. Mechanistic and in vitro data support antiviral properties; dedicated clinical trials on wart resolution are lacking in the authoritative literature.
Greater Celandine (Chelidonium majus)
Traditional Use
Greater celandine has a long history in European folk medicine as a topical remedy for warts. Homeopathic remedies such as Thuja occidentalis are popular alternative treatments. Pharmacies offer a range of over-the-counter standardized greater celandine tinctures, callus and wart drops containing salicylic acid, propolis solutions, and cryotherapy sprays. The yellow-orange milky sap of celandine, containing alkaloids including chelidonine and berberine, has been applied directly to warts in European folk practice for centuries.
Scientific Evidence
Robust human clinical trial data specifically for greater celandine as a wart treatment are not available in the high-quality peer-reviewed sources searched. Its alkaloids are pharmacologically active, but the transition from traditional topical use to clinically validated outcomes has not been rigorously established in the peer-reviewed literature.
Evidence strength: Weak. Traditional documentation is extensive in European ethnobotany; clinical trial evidence is not established through authoritative sources.
Dietary and Lifestyle Factors
Overall Diet Quality and Fruit/Vegetable Intake
Women who did not consume total fruits, whole fruits, or green vegetables and beans had a significantly higher risk of high-risk HPV infection than women who complied with the Dietary Guidelines for Americans. An increase in fruits and greens and beans leads to a decrease in HPV infection, consistent with antioxidant studies indicating that dietary antioxidants (vitamins A, B2, E, and folate) are inversely associated with high-risk HPV infection. These antioxidants can be found in dark-green vegetables such as spinach, kale, and broccoli, beans such as lima beans and soybeans, and fruits such as oranges, grapes, blueberries, and mango.
Antioxidants, certain vitamins, dietary patterns rich in fruits and vegetables, and functional foods may offer protective benefits against HPV and its progression. In contrast, diets with a high glycemic load or pro-inflammatory properties may contribute to disease progression.
Smoking
In both genders, smoking is associated with higher incidence and prevalence rates for HPV infection, whereas the latter responds to a dose-effect relationship. A cohort study showed that smokers were significantly more likely to have persistent HPV infections compared to non-smokers. "In summary, smoking increases the risk for HPV infection by impairing immunity and reducing antibody titers. This diminishes clearance — and thus increases the persistence of HPV infection — and increases the risk of precancerous lesions and cancers."
Physical Activity
Lifestyle factors and metabolic health play a crucial role in modulating immune responses. One study demonstrated that higher physical activity levels were associated with a reduced risk of HPV infection, likely due to enhanced immune function. Mechanism is proposed via modulation of mucosal immunity and reduction of systemic inflammation; however, RCT evidence specifically linking exercise to wart resolution is not established.
Micronutrient Status and DNA Methylation
Nutrients assessed in a large systematic review and meta-analysis included vitamins A, C, D, E, K, B-complex (particularly B6, B12, and folate), carotenoids (β-carotene, lycopene, lutein), and minerals like selenium, zinc, and calcium. Higher dietary intake or serum levels of micronutrients were associated with reduced persistence of HPV and decreased risk of CIN and cervical cancer.
It is important to consider that a significant proportion of the studies included are observational in nature, which limits the ability to infer causality between specific nutrients and HPV-related disease prevention. While antioxidants, folate, and carotenoids have been frequently associated with a lower risk of cervical disease, the limited number of randomized clinical trials reduces the strength of the evidence and prevents definitive conclusions regarding their protective effects.
Vaginal Microbiota and Dysbiosis
After 12–30 months of HPV infection, 70–90% of patients can be cleared naturally, but there are still a small number of patients with high-risk HPV infection who cannot eliminate it by themselves, and can develop into cervical intraepithelial neoplasia, eventually progressing to invasive cervical cancer. Dysbiosis — a reduction in protective Lactobacillus species — has been identified as a factor correlated with HPV persistence, though the direction of causality and the specific nutritional determinants of microbiome composition in this context remain areas of active investigation.
Summary of Evidence Strength
- Topical sinecatechins (Veregen / Polyphenon E ointment): Strong evidence; FDA-approved; multiple Phase 3 RCTs for external genital and perianal warts.
- Zinc (oral and topical): Moderate evidence; RCTs exist, with strongest effects in zinc-deficient populations; systematic reviews support efficacy in viral warts.
- Folate and Vitamin B12: Moderate-to-high evidence (GRADE: High in meta-analysis) for CIN and HPV persistence; evidence for common cutaneous warts is indirect.
- Vitamin D: Mixed and inconsistent evidence; positive meta-analytic findings for HPV-related cervical lesions (GRADE: High for CIN outcomes); unclear direct relevance to warts.
- Vitamin E, Vitamin A, Carotenoids, Selenium: Moderate observational evidence for HPV-associated disease; not studied specifically in common warts.
- Vitamin C: Weak evidence; recognized biological role in immunity but insufficient RCT data.
- Thuja, garlic, celandine: Weak evidence; traditional use well-documented; high-quality clinical trials in warts are lacking.
- Oral green tea / EGCG: Weak evidence; Phase II RCT showed no benefit over placebo for internal HPV clearance.
- Smoking cessation: Supported by consistent epidemiological data across multiple study designs as a modifiable factor for HPV persistence and wart recurrence.
- Diet quality (fruits, vegetables, antioxidants): Moderate observational evidence for reduced HPV persistence; RCT-level evidence for wart resolution specifically is limited.
References
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