Blackcurrant for blood sugar and metabolic health
What it found
Blackcurrant may help lower blood sugar and insulin after meals, and repeated intake may slightly improve insulin sensitivity, but human studies are small and short.
Most evidence for how it works comes from lab and animal studies.
What they found
Studies in people
Blood sugar after meals
In healthy adults, a single dose of blackcurrant lowered early blood sugar and insulin after a high-carbohydrate meal. The effect depended on the dose and the form of blackcurrant used.
Insulin sensitivity
Eight days of a New Zealand blackcurrant extract improved insulin sensitivity by 22% and lowered C-reactive protein in people. Five weeks of an anthocyanin-rich blackcurrant extract reduced oxidative stress markers and raised antioxidant capacity.
Animal and lab studies
How it may work
In lab tests, blackcurrant compounds slowed carbohydrate-digesting enzymes and blocked glucose transporters. In diabetic mice, blackcurrant extract increased a key energy sensor in muscle and moved more glucose transporters to the cell surface, lowering blood sugar.
Inflammation and oxidative stress
In mice fed a high-fat diet, blackcurrant extract reduced fat mass, fat cell size, and markers of inflammation in fat tissue. It also lowered inflammatory cytokines in immune cells taken from these mice.
Studies in people and animals
Gut bacteria
A four-week blackcurrant drink increased Lactobacilli and Bifidobacteria and lowered a bacterial enzyme and stool pH in people. In mice and rats, blackcurrant extract also changed the gut microbiome.
Other findings
How much gets into the body
Even a large dose of blackcurrant anthocyanins led to very low levels in the blood, and most is broken down by gut bacteria into other compounds. This may explain why human effects are modest and vary between people.
What the authors conclude
“Ribes nigrum should currently be considered a complementary dietary strategy rather than a replacement for evidence-based antidiabetic treatment.”
Also in their conclusions
- They say that current evidence does not support specific therapeutic recommendations regarding dose, formulation, treatment duration, or modification of established antidiabetic therapy.
- They conclude that Ribes nigrum should currently be considered a complementary dietary strategy rather than a replacement for evidence-based antidiabetic treatment.
- They call for standardized formulations, metabolite-level pharmacokinetic characterization, and adequately powered long-term randomized controlled trials that separate blackcurrant-specific effects from those of anthocyanins in general.
How it was done
Type 2 diabetes is a major global health problem, and current drugs do not work well enough for many people. The authors wanted to see if blackcurrant, a polyphenol-rich berry, could be a useful dietary add-on for managing blood sugar and metabolic health.
The authors searched scientific databases for studies on blackcurrant and metabolic outcomes, including lab, animal, and human studies. They looked at how blackcurrant is absorbed and used by the body, and they assessed the quality of the human trials.
What it can’t tell you
- Most human studies are small and short, so they cannot show whether blackcurrant improves long-term outcomes like HbA1c or prevents diabetes.
- Many studies used mixed-berry or multi-component products, so the effects cannot be attributed to blackcurrant alone.
- Lab and animal results cannot show what happens in people, especially at the low amounts that reach the bloodstream after eating blackcurrant.
Who paid
- Conflicts
- The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
- Authors work at
- Karolinska Institute, Sweden; Institute of Genetics and Animal Biotechnology, Poland; Lovely Professional University, India
The paper
- Title
- The Nutraceutical Potential of Blackcurrant ( Ribes nigrum ) for Glycemic Control and Metabolic Health: Mechanistic and Translational Insights
- Type
- ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Licence
- CC BY. Words in quotation marks are the authors’; the rest is our summary.
- Cite
- Religa P, Pieczynska-Kovacs MD, Łazarczyk M, et al (2026). The Nutraceutical Potential of Blackcurrant ( Ribes nigrum ) for Glycemic Control and Metabolic Health: Mechanistic and Translational Insights. Nutrients. doi:10.3390/nu18172852Free full textPubMed 42739024DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error