Blackcurrant drinks and blood sugar in healthy adults
What it found
In two trials in healthy adults, a lower-dose blackcurrant drink slightly slowed the early rise in blood sugar after a high-carb meal, but the effect on overall blood sugar was small.
Adding orange extract or orange pulp did not boost the effect.
What they found
Studies in people
Early blood sugar
The lower-dose blackcurrant drink (800 mg polyphenols) reduced the early rise in blood sugar over the first 30 minutes compared with placebo. The higher dose (1600 mg) did not.
Overall blood sugar
Over the full postprandial period, there was no difference in total blood sugar response between any blackcurrant drink and placebo.
Insulin and gut hormone
Both blackcurrant drinks lowered insulin secretion in the first 30 minutes and reduced the gut hormone GIP for up to 120 minutes compared with placebo.
Orange extract combination
Adding sweet orange extract to blackcurrant did not enhance the blood sugar lowering effect. The orange extract alone had no significant effect.
Orange pulp combination
Blackcurrant plus orange pulp reduced early blood sugar, insulin and GIP compared with placebo. Orange pulp alone did not lower blood sugar.
Appetite and cognitive function
Appetite measures were unaffected by any drink. Blackcurrant plus orange pulp improved some indicators of cognitive function but not all.
What the authors conclude
“The impact of (poly)phenol-rich BC extracts on total postprandial glycaemia in healthy participants was minimal and not enhanced when administered in combination with an orange (poly)phenol extract or orange pulp.”
Also in their conclusions
- They say the impact of polyphenol-rich blackcurrant extracts on total postprandial glycaemia in healthy participants was minimal.
- They report that this effect was not enhanced when the extracts were given with an orange polyphenol extract or orange pulp.
How it was done
The authors wanted to see whether combining blackcurrant extracts with other fruit extracts or fruit fibre would slow the rise in blood sugar more than blackcurrant alone.
In two randomised, double-blind, crossover trials, healthy adults drank 200 mL test drinks followed by a high-carb meal. Twenty-nine adults completed the first trial and 37 completed the second.
What it can’t tell you
- The trials only looked at healthy adults after a single meal, so they cannot show what happens over longer periods or in people with diabetes.
- The cognitive function tests were a secondary measure and the trials were not designed to detect changes in them.
Who paid
- Authors work at
- King's College London, UK; Instituto de Saúde Ambiental, Portugal
The paper
- Title
- Acute effects of drinks containing blackcurrant and citrus (poly)phenols and dietary fibre on postprandial glycaemia, gut hormones, cognitive function and appetite in healthy adults: two randomised controlled trials
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Licence
- CC BY. Words in quotation marks are the authors’; the rest is our summary.
- Cite
- Pinto AM, Hobden MR, Brown KD, et al (2023). Acute effects of drinks containing blackcurrant and citrus (poly)phenols and dietary fibre on postprandial glycaemia, gut hormones, cognitive function and appetite in healthy adults: two randomised controlled trials. Food & function. doi:10.1039/d3fo03085gFree full textPubMed 37902089DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error