grosella negra

Black Currant (Ribes nigrum L.): A Comprehensive Reference

1. Identity, Botanical Classification, and Common Forms

Botanical and Chemical Identity

Ribes nigrum (Grossulariaceae), commonly known as black currant, blackcurrant, and cassis, is a fruit-producing shrub grown primarily for its dark purple berries. Black currants are berries native to central and northern Europe and Asia, belonging to the family Grossulariaceae. Additional common names include European black currant, Groseille Noir, Grosella Negra, Nabar, and Ribes Nero. The dried leaf preparation is sometimes referred to by its Latin pharmacopoeial name Ribes Nigri Folium.

The fruit of the blackcurrant is round-shaped, dark purple, bittersweet, and seed-containing edible berries. The berries are astringent and tart with a high pectin and acid content.

Common Preparations and Forms

Black currants are usually consumed in processed forms such as juices, jam, jelly, pies, and smoothies. In the supplement industry, commercial preparations include standardized berry extracts (typically standardized to anthocyanin content), dried berry powder, berry juice concentrate, leaf tea infusions, and black currant seed oil in softgel capsules. Standardization of commercial products has usually been related to anthocyanin and/or vitamin C content.

Although berries represent the most important part of currant plants, the buds and leaves are becoming of interest as potential sources of biologically active compounds. Black currant buds are also used for essential oil production for application in the cosmetics and perfume industries.

2. Historical and Traditional Use

Origins and Early Cultivation

Black currants (Ribes nigrum) are small, dark berries native to central and northern Europe and Asia. They have been cultivated for centuries, with evidence of their use dating back to the 11th century. Blackcurrant was cultivated in the 11th century in Russia. In the 17th century, wider cultivation began. The earliest documented cultivation of black currant in European gardens dates to the 17th century, when Flemish and Dutch horticulturists began selecting plants for larger, more flavorful berries. By the 18th century, black currant was a fixture in kitchen gardens across Britain, France, and Germany.

Its cultivation spread to Russia, where it became deeply embedded in folk cuisine and medicine under the name smorodina. Russian monasteries in particular maintained extensive black currant plantings for both culinary and medicinal purposes.

Currants' first record of cultivation and human consumption can be traced back to the Renaissance in Europe (14th to 17th centuries), when they started being grown in farms and gardens. Old herbalist texts from the 1600s describe the medicinal properties of currants. Currants have been cultivated in Europe since around the 1600s, with the use of black currant leaves in medicinals and teas dating back to 1636.

Traditional Medicinal Uses in Europe

Historically, black currants have been used in traditional European medicine for a variety of ailments. They were believed to possess diuretic, diaphoretic (sweat-inducing), and anti-inflammatory properties. In traditional European folk medicine, black currant leaves are used in the treatment of rheumatism, arthritis, and respiratory problems.

Black currant juice was used for a variety of inflammatory conditions such as fevers and sore throat, as well as "calculous affections" (the formation of mineral stones in organs such as kidneys and gallstones) and edema (swelling caused by fluid retention). Blackcurrant leaf infusions were traditionally used as a diuretic and to alleviate symptoms of rheumatism and gout. In some traditional practices, black currant preparations were applied topically to treat skin conditions like eczema and wounds.

Traditional herbalists across northern Europe used every part of the plant. Leaves were made into infusions to treat gout, kidney disorders, and respiratory infections. Black currant fruits have been used in Asian and European traditional medicine for the treatment of a variety of diseases.

Wartime and Modern Cultural Significance

During World War II, when citrus imports to the UK were restricted, black currants became an essential source of vitamin C. The British Government promoted the cultivation of the blackcurrant plant, as it became suitable to grow in the climate of the UK. Currant cultivation experienced a boom in the post-World War II years when they began to be grown in areas where it was difficult to grow citrus fruit.

In the United States, black currants were less common for much of the 20th century due to cultivation restrictions related to white pine blister rust concerns. Japan currently imports significant quantities of New Zealand's blackcurrants to produce dietary supplements and other functional food products. They are also very popular in Eastern Europe, and Russia is the world's top producer.

3. Key Constituents and Active Compounds

Anthocyanins

Black currant (Ribes nigrum L., Grossulariaceae) is known to contain high amounts of anthocyanins (250 mg/100 g fresh fruit). Anthocyanins are the major group of phenolic compounds in black currants, representing almost 80% of the phenolics content.

Fifteen anthocyanin structures have been reported from an extract of black currant berries (Ribes nigrum L.). These are the 3-O-glucosides and the 3-O-rutinosides of pelargonidin, cyanidin, peonidin, delphinidin, petunidin, and malvidin, cyanidin 3-O-arabinoside, and the 3-O-(6''-p-coumaroylglucoside)s of cyanidin and delphinidin. The four main pigments — the 3-O-glucosides and the 3-O-rutinosides of delphinidin and cyanidin — made up more than 97% of the total anthocyanin content. The amounts of anthocyanin rutinosides were found to be higher than the amounts of the corresponding glucosides for all detected pigments.

Other Polyphenols and Phenolic Acids

Numerous bioactive and flavoring components are present, including vitamins, minerals, polyphenols, polyunsaturated fatty acids (PUFA), organic acids, vitamins C and E, soluble and insoluble dietary fibers, tannins, and soluble sugars. The main flavonol found in black currant berries and leaves is quercetin, followed by myricetin, while kaempferol is present in very small amounts. The most abundant phenolic acid in berry extract is caffeic acid, while leaf extract is dominated by ferulic acid. Currant leaves contain tannins and phenolic compounds such as anthocyanins, flavonols, flavan-3-ols, and phenolic acids.

Vitamin C

Blackcurrants are high in vitamin C, providing 181 mg per 100 g, equivalent to 226% of dietary reference values. According to the Ciqual 2020 table, blackcurrants are, after guava, the fruit that contains the most vitamin C. Vitamin C content is the major contributor to the antioxidant capacity of black currant.

Seed Oil Fatty Acids (GLA, SDA, ALA)

Black currant seed oil has one of the highest concentrations of the omega-6 fatty acid gamma-linolenic acid (GLA) found in any plant source. It is also a rich source of alpha-linolenic acid (ALA), a plant-based omega-3 fatty acid precursor, and stearidonic acid (SDA), which the body converts into EPA more efficiently than ALA alone.

Linoleic acid (LA) is the major component of currant seed oil, with contents ranging from 32.7–46.9% of total fatty acids, followed by alpha-linolenic acid (ALA; 2.9–32.0%), oleic acid (9.8–19.9%), gamma-linolenic acid (GLA; 3.3–18.5%), palmitic acid (4.4–8.1%), stearidonic acid (SDA; 2.2–4.7%), and stearic acid (1.2–2.4%).

Supplemental GLA sources include the oils of borage (Borago officinalis), at 20–26% GLA; black currant (Ribes nigrum), at 15–18%; and evening primrose (Oenothera biennis), at 8–12%. According to Tufts researchers, black currant seed oil is a preferred source because it contains 13–16% of the omega-3 fatty acid alpha-linolenic acid as well as GLA.

Minerals

Phosphorus (P), potassium (K), and calcium (Ca) are the principal mineral constituents of blackcurrant.

4. Mechanisms of Action

Antioxidant Activity

Blackcurrants contain high amounts of anthocyanin polyphenols, which have antioxidant and anti-carcinogenic health benefits. Black currant is known as a rich source of antioxidants, largely due to its high content of phenolic compounds, especially anthocyanins. Black currant extract has recently been found to be the second most effective among nine different berry extracts studied for their free radical scavenging activity. Blackcurrant has DPPH and ABTS radical scavenging characteristics.

Anti-Inflammatory Pathways

Dietary antioxidants such as anthocyanins are helpful in the prevention and control of various diseases by counteracting the imbalance of oxidative and antioxidative factors in living systems. Constituents present in black currant juice have been found to exert a number of health-promoting effects, including immunomodulatory, antimicrobial, and anti-inflammatory actions, inhibition of low-density lipoprotein, and reduction of cardiovascular diseases.

GLA from black currant seed oil is converted in the body to dihomo-gamma-linolenic acid (DGLA), which then produces series-1 prostaglandins, particularly prostaglandin E1 (PGE1). This prostaglandin pathway is considered a key mechanism underlying the anti-inflammatory effects associated with GLA-containing oils.

Ocular Mechanisms

Mechanistically, cyanidin-3-glycosides stimulate the regeneration of rhodopsin, and delphinidin-3-rutinoside relaxes bovine ciliary smooth muscle by activating the endothelin B receptor and the NO/cyclic guanosine-5'-monophosphate pathway. Clinical trials have reported endothelium-dependent vasorelaxation induced by blackcurrant leading to the improvement of retinal blood circulation in normal-tension glaucoma patients.

Phytoestrogenic Activity

Research has analyzed the phytoestrogenic effects of blackcurrant extract (BCE) in breast cancer (MCF-7) and human endometrial cancer (Ishikawa) cell lines that over-express estrogen receptor alpha (ERα), as well as in immature female rats. Microarray analysis showed that BCE activated the ERα pathway, and quantitative-PCR confirmed that BCE and four types of anthocyanins up-regulated genes downstream of ERα. These results suggest that blackcurrant anthocyanins act as phytoestrogens in vitro and in vivo. This work is preliminary and based on cell and animal models; its clinical relevance in humans remains unestablished.

Bioavailability of Anthocyanins

Blackcurrants are rich in anthocyanins, with more than 97% of total anthocyanins comprising delphinidin and cyanidin glycosides. Dietary anthocyanins are rapidly absorbed, with concentrations of their glycosylated forms peaking in blood plasma 1 hour after ingestion, then declining thereafter. Anthocyanins and flavonoids in black currant berries and juice have low bioavailability. Protocatechuic acid concentration increases significantly after ingestion of blackcurrant extract, and significant quantities of biologically active compounds circulate in the blood following ingestion of a blackcurrant extract containing delphinidin-3-O-rutinoside and cyanidin-3-O-rutinoside.

5. Scientific Evidence by Area of Use

5.1. Eye Health: Visual Fatigue, Dark Adaptation, and Glaucoma

This is the area with the largest body of human clinical trial evidence for black currant preparations. Multiple randomized controlled trials (RCTs) have been conducted, primarily by Japanese research groups.

Dark adaptation and screen-induced eye fatigue: The effects of oral intake of a black currant anthocyanosides (BCA) concentrate on dark adaptation, video display terminal (VDT) work-induced transient refractive alteration, and subjective asthenopia symptoms (visual fatigue) were examined in a double-blind, placebo-controlled, crossover study with healthy human subjects. Intake of BCA at three dose levels (12.5, 20, and 50 mg/subject; n=12) appeared to bring about dose-dependent lowering of the dark adaptation threshold, with a statistically significant difference at the 50 mg dose (p = 0.011).

Glaucoma — Visual Field Preservation: To examine the influence of black currant anthocyanins (BCACs) on the disease progression of open-angle glaucoma (OAG), a randomized, placebo-controlled, double-masked trial was conducted in 38 patients with OAG treated by antiglaucoma drops. BCACs (50 mg/day, n=19) or their placebos (n=19) were orally administered once daily for a 24-month period. Systemic blood pressure, pulse rates, intraocular pressure (IOP), ocular blood circulation by laser-speckle flowgraphy, and Humphrey visual field mean deviation (MD) were measured throughout. As the main outcome measurement, the difference between groups in MD deterioration was evaluated; a statistically significant difference was observed between the treatment groups in mean change from baseline in MD 24 months after therapy (p = 0.039).

Glaucoma — Endothelin-1 Normalization: A subsequent study based on the same 24-month randomized, placebo-controlled, double-masked trial revealed that oral administration of black currant anthocyanins (BCACs) slowed down the visual field deterioration and elevated ocular blood flow of open-angle glaucoma (OAG). In an initial clinical trial, systemic administration of BCACs (50 mg/day) to patients with OAG (n=30) for 6 months caused a significant increase in blood flows at the optic nerve head (p < 0.05).

Digital Eye Fatigue RCT: A randomized, double-blind, placebo-controlled clinical trial was conducted in the United States in 2021. The study included 61 adult female participants aged 30–59 years who worked or studied 6 hours or more per day in front of a screen. The intervention group consumed two capsules of standardized black currant extract each day for 10 weeks (totaling 445 mg per day), standardized to contain 11% anthocyanins, providing a daily dose of 50 mg of anthocyanins.

Evidence Strength — Ocular Health: Multiple small-to-medium RCTs support improvement in ocular blood flow and mitigation of visual fatigue at doses around 50 mg anthocyanins per day. The glaucoma trial by Ohguro et al. (2012) is the strongest individual study (n=38, 24 months, double-masked), but sample sizes across the field remain limited. Evidence is conflicting regarding the benefits of black currant as an antioxidant source and in night- and fatigue-related visual impairment. Further large-scale RCTs are needed before definitive conclusions can be drawn.

5.2. Cardiovascular Health and Blood Pressure

Recent cell and animal studies suggest the potential of blackcurrants (Ribes nigrum) as a dietary agent that may reduce the risk of cardiovascular disease (CVD) by improving dyslipidemia, oxidative stress, and inflammation.

Blood Pressure — Meta-Analysis: A systematic review and meta-analysis was designed to summarize studies on the effects of raspberry and blackcurrant consumption on blood pressure. Eligible studies were detected by searching multiple databases until December 2022, and a random-effects model was applied. Overall, the impact of raspberry and blackcurrant on blood pressure was reported in ten randomized controlled trials (420 subjects).

Blackcurrant Seed Oil and Blood Pressure: A separate line of clinical investigation has examined black currant seed oil specifically. A clinical trial (PMID: 8895037) examined resting blood pressure and cardiovascular reactivity to mental arithmetic in mild hypertensive males supplemented with blackcurrant seed oil, indicating interest in this preparation for cardiovascular endpoints.

Animal Evidence: An intravenous injection of black currant juice (0.33–166.5 mg/kg) in rabbits induced a significant and dose-dependent decrease of arterial blood pressure and heart rate. The black currant juice decreased arterial blood pressure by 22.33% ± 3.76% (p < 0.05) and heart rate by 17.18% ± 2.93% (p < 0.05). This is animal evidence and should not be extrapolated directly to humans.

Menopause Transition — Pilot RCT (Lipids and Inflammation): A pilot randomized controlled clinical trial aimed to examine the effects of blackcurrant anthocyanin extract supplementation on biomarkers of CVD risk in healthy adult women in menopause transition. The effects of supplementation on body composition, fasting blood lipids, and biomarkers of inflammation and oxidative stress were evaluated. Thirty-eight eligible peri- and early postmenopausal women aged 45–60 completed the entire trial, in which they were randomly assigned to a placebo (control group), 392 mg/day (low BC group), or 784 mg/day (high BC group). This study is notable as a human RCT in a clinically relevant population, though its pilot scale limits generalizability.

Evidence Strength — Cardiovascular: The cardiovascular case for black currant seed oil rests primarily on GLA's prostaglandin-related mechanisms rather than direct endpoint studies. Human clinical data for whole-berry preparations show early promise but remain limited in scale and consistency.

5.3. Exercise Performance and Recovery

A growing body of research, primarily from New Zealand, has examined black currant anthocyanin extracts in the context of exercise.

Narrative Review (2024): A narrative review focused on observations with intake of anthocyanin-rich blackcurrant supplements on whole-body exercise performance and exercise recovery. This review included 17 studies with a randomized placebo-controlled crossover design (10 studies on performance, 8 on recovery effects) and 1 with a randomized placebo-controlled parallel group design. Among the performance studies, 6 studies (60%) reported positive effects, 3 studies (30%) reported no significant effects, and 1 study (10%) reported a mixed outcome. Among the recovery studies, 7 studies (78%) reported positive effects, 1 study (11%) reported no significant effects, and 1 study (11%) reported a negative effect.

Studies with intake of supplements made from New Zealand blackcurrants (dose: 1.8–3.2 mg/kg and 105–315 mg anthocyanins, acute to 7-day intake) provided meaningful but not always consistent effects on continuous and intermittent exercise performance tasks (i.e., rowing, cycling, and running) and markers for exercise recovery.

Oxidative Stress — Pilot RCT: It was previously reported that a single consumption of a 3.2 mg/kg New Zealand blackcurrant anthocyanin-rich extract (BAE) 1 hour before 30 minutes of rowing exercise attenuated moderate exercise-mediated oxidative stress and supported innate immunity. A subsequent 5-week daily consumption study evaluated whether this efficacy was maintained. On week 1, a single consumption of BAE 1 hour before a 30-minute row mediated a significant (p < 0.05) 46% reduction in post-exercise-induced malondialdehyde (MDA) by 2 hours compared to a 30% reduction in the placebo group.

Blood Flow During Sedentary Sitting: A crossover study examined the acute effects of anthocyanin-rich New Zealand blackcurrant extract and placebo on hemodynamics during 120 minutes of sedentary sitting in healthy males. Ten healthy males ingested either blackcurrant extract (1.87 mg total anthocyanins per kg bodyweight) or placebo powder, with heart rate, blood pressure, and forearm blood flow measured at intervals.

Evidence Strength — Exercise: A mechanistic understanding for the beneficial exercise effects of anthocyanins for athletes and physically active individuals is still limited. Future work requires a better understanding of the specific types of anthocyanins and anthocyanin-induced metabolites and their effects on altering cell function that can enhance exercise performance and recovery. Most studies are small, short-duration crossover trials. Overall evidence is promising but preliminary.

5.4. Immune Function

Blackcurrant anthocyanins have been shown to exhibit health properties independent of their antioxidant capability using both in vitro cell studies and human nutrition studies, whereby consumption of blackcurrant anthocyanin compounds has been reported to support innate immunity.

Seed Oil and Elderly Immune Function: Examining the effects of black currant seed oil (vs. placebo) in healthy elderly subjects, researchers from Tufts found that GLA reduced levels of PGE2 and improved immune function. This was a randomized, controlled study published in the American Journal of Clinical Nutrition (Wu D et al., 1999; 70:536–543).

Atopic Dermatitis Prevention: A study published in Pediatric Allergy and Immunology found that black currant seed oil supplementation in nursing mothers was associated with higher IFN-gamma and lower IL-4 levels in breast milk compared to placebo. Oil and juice extracts have also exhibited limited antimicrobial and prebiotic activities, as well as potential benefit in preventing infant atopic dermatitis.

Evidence Strength — Immune: Evidence here is composed of a small number of human studies with limited sample sizes. Findings are mechanistically plausible but not yet sufficient to support firm clinical conclusions.

5.5. Rheumatoid Arthritis and Anti-Inflammatory Effects

Two small published trials showed some benefit in rheumatoid arthritis, but black currant was not compared to a gold standard. Long-term safety and efficacy have not been studied for any of the above potential uses.

The mechanism proposed for joint inflammation is largely through GLA's conversion to DGLA and subsequent production of series-1 prostaglandins, which compete with pro-inflammatory arachidonic acid metabolites. Deficiency of long-chain PUFAs is often seen in patients with chronic diseases such as diabetes, hypercholesterolemia, rheumatoid arthritis, autoimmune disorders, Crohn's disease, and cancer. Increasing clinical evidence has shown that dietary supplementation of PUFAs, such as GLA, can provide beneficial effects and alleviate many symptoms associated with chronic diseases.

5.6. Bone Health

A pilot double-blind, randomized, placebo-controlled clinical study with blackcurrant supplementation for six months in peri- and early postmenopausal women aged 45–60 aimed to evaluate the dose-dependent effects of blackcurrant supplementation on bone density and its relationship to bone metabolism. The primary endpoint was whole-body bone mineral density (BMD). Changes in serum markers of bone metabolism following blackcurrant supplementation were also assessed to delineate underlying mechanisms. This study represents early-phase clinical evidence; further replication is needed.

5.7. Antimicrobial Activity

Black currant juice and oil extracts have exhibited limited antimicrobial activities. Preclinical data from cell studies have reported activity against certain pathogens, including anti-herpes virus properties. However, no robust human clinical trials have validated antimicrobial clinical outcomes.

5.8. Chemopreventive Activity (Preclinical Only)

Anthocyanins are known to possess potent anticarcinogenic properties against several cancers, thus demonstrating potential for cancer prevention. Black currant fruits have a high anthocyanin content, known to possess various pharmacological effects including alleviation of chronic oxidative stress and inflammation. In contrast to a large volume of literature on the health benefits of black currant, limited evidence on antitumor effects of black currant exists with virtually no data on the prevention of experimental carcinogenesis in humans.

In a rodent model of liver carcinogenesis, black currant skin extract (BCSE) dose-dependently decreased the incidence, total number, multiplicity, size, and volume of preneoplastic hepatic nodules. The anti-hepatocarcinogenic effect of BCSE was confirmed by histopathological examination. Immunohistochemical analysis of proliferating cell nuclear antigen and DNA fragmentation revealed BCSE-mediated inhibition of abnormal cell proliferation and induction of apoptosis. This is exclusively preclinical (animal) evidence; no human studies on cancer prevention with black currant are available.

6. Body Systems and Health Areas

• Visual System: Ocular blood flow, retinal circulation, dark adaptation, visual fatigue, and glaucoma progression — supported by multiple small-to-medium human RCTs.
• Cardiovascular System: Endothelial function, blood pressure, lipid profiles (LDL, HDL, triglycerides), and oxidative stress — evidence from human pilot RCTs and meta-analyses, though effect sizes and consistency remain under investigation.
• Musculoskeletal System: Rheumatoid arthritis and joint inflammation (via GLA/DGLA pathway); small clinical trials with limited comparators. Bone density explored in a pilot RCT.
• Immune System: Innate immunity, cytokine modulation, and atopic dermatitis prevention — small human studies and mechanistic data available.
• Exercise and Sports Recovery: Reduction of oxidative stress, improved peripheral blood flow, and faster recovery — supported by a body of small crossover RCTs, mostly with New Zealand blackcurrant extract.
• Metabolic/Endocrine: Potential phytoestrogenic activity via ERα; relevant in menopausal contexts, though this is preliminary and primarily from cell and animal models.
• Antimicrobial (preclinical): In vitro evidence for activity against certain bacteria and viruses, not yet validated in clinical trials.

7. Dosage Forms and Reported Dosages

Limited clinical trial data exist to provide dosage recommendations. The following dosages reflect those specifically reported in published studies and databases:

• Anthocyanin extract (berry), ocular health: Black currant anthocyanins (BCACs) at 50 mg/day were orally administered once daily for a 24-month period in a randomized controlled glaucoma trial.
• Anthocyanin extract (berry), digital eye fatigue: 445 mg/day of standardized black currant extract for 10 weeks, standardized to 11% anthocyanins, providing 50 mg anthocyanins per day.
• Anthocyanin extract (berry), exercise: Doses of 1.8–3.2 mg/kg bodyweight and 105–315 mg anthocyanins, administered acutely to 7-day duration, were used in exercise studies.
• Anthocyanin extract (berry), menopause/CVD: Doses of 392 mg/day and 784 mg/day of blackcurrant supplementation were used in a 6-month pilot RCT in peri- and early postmenopausal women aged 45–60.
• Leaf tea: A tea made from 2 to 4 g of chopped leaves can be administered several times per day.
• Black currant seed oil (GLA): Dosages for black currant seed oil as a GLA source in clinical contexts have ranged from 2 to 10 grams per day.

8. Safety Considerations and Drug Interactions

General Safety

Black currant is likely safe when used as food, or when black currant berry or seed oil is used appropriately as medicine. Not enough is known about black currant dried leaf to rate its safety definitively.

Pregnancy and Lactation

There is not enough reliable information about the safety of taking black currant if you are pregnant or breast-feeding; the safer approach is to avoid supplemental use.

Anticoagulant and Antiplatelet Drug Interactions

Theoretically, black currant seed oil might increase the risk of bleeding if used in combination with anticoagulant or antiplatelet drugs. Gamma-linolenic acid (GLA), a constituent of black currant seed oil, appears to have antiplatelet effects. Black currant products may theoretically increase bleeding risk through antiplatelet effects of gamma-linolenic acid.

Medications that slow blood clotting carry a moderate interaction rating. Black currant might slow blood clotting, and taking black currant along with medications that also slow clotting might increase the chances of bruising and bleeding. Relevant medications include aspirin, clopidogrel (Plavix), ibuprofen, naproxen, dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.

Anesthesia / Surgical Concern

There is a moderate interaction concern with medications used during surgery (anesthesia). There is one report of seizure during surgery in someone who took a supplement containing the fatty acid gamma-linolenic acid. This interaction is rated as moderate and is based on limited case-level evidence.

Bleeding Disorders

Black currant might slow blood clotting. There is some concern that it might increase the risk of bruising and bleeding in people with pre-existing bleeding disorders.

Blood Pressure

The cardiovascular case for black currant seed oil rests primarily on GLA's prostaglandin-related mechanisms. Black currant seed oil may theoretically affect platelet aggregation based on its fatty acid activity. This is a precautionary consideration rather than a firmly established clinical interaction.

Distinction Between Berry and Seed Oil Safety Profiles

Black currant berry preparations, particularly those rich in anthocyanins, have shown effects on vascular tone and circulation in research. However, the berry anthocyanins and the seed oil are distinct components of the plant, and the evidence for each should not be treated as interchangeable.

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