Black Currant
Black currant (Ribes nigrum) is a shrub whose dark berries are used for juice and whose seeds give an oil containing gamma-linolenic acid.
Also listed as Blackcurrant, Black Currant Seed Oil, Cassis, European Black Currant
What it is studied for
The strongest rated effects first. Bars show the size of the effect, the letter grades the evidence, and each rating lists the studies behind it.
Which part of the plant are you buying?
Blackcurrant, Ribes nigrum, appears as whole berries, anthocyanin-rich fruit preparations, seed oil and leaf medicines. Research on the fruit pigments includes glaucoma; seed oil has been tested in rheumatoid arthritis. EMA’s traditional-use assessment concerns the leaves, not the berries or oil. 1 2 3 4
Why people take it
SuppCo community snapshot, 2026-09-28. Reasons for use are not evidence that it works.
Questions people ask
Are berry extract and seed oil interchangeable?
No. The glaucoma trial tested anthocyanins, while the arthritis trials tested seed oil. Their results concern those preparations. 2 3
Can blackcurrant replace glaucoma drops?
The positive trial kept participants on glaucoma drops. It tested an addition to treatment, not a replacement. 2
Does traditional use mean proven efficacy?
No. EMA’s leaf indication rests on long-standing use; adequate clinical studies were lacking at assessment. 4
How long can urinary symptoms be watched?
EMA advises medical review if symptoms persist beyond two weeks during leaf treatment, or worsen. Fever, painful urination or blood in the urine warrants earlier assessment. 5