The supplement increased fat burn rates by up to 200% and enhanced reductions in blood pressure after exercise by up 11%, with the lead researcher suggesting its use as a safe nutritional intervention to rival expensive Type 2 Diabetes drugs.
In the first comparative study of its kind, the berry supplement accelerated fat burning in the group by an average 28%, with the highest male responder reaching 204%, and female responder reaching 216%. The greatest effect was seen in women carrying more body fat.
“The message is clear, we have proof of principle that New Zealand blackcurrant extract is powerful and reliable for increasing fat metabolism and reducing cardiovascular disease risk factors, such as blood pressure,” said lead researcher, Dr Matthew Cook, describing the study as a ‘watershed moment’ in blackcurrant research.
“We’ve shown here that women who carry more fat, have the highest magnitude of change to blackcurrant. The great news is that it works for everyone, and some people respond more highly.
“This a high-impact discovery from a large dataset that had excellent controls.”
The researchers from the University of Worcester concluded one week’s supplementation with the berry supplement led the group to burn, on average, an additional 3.6g of fat in one hour of exercise.
Across a month, if users were to exercise five times a week, this could equate to an average of approximately 72 grams of fat.
Cook said: “If you can increase fat burning during exercise, over a prolonged period of time, that could equate to greater fat loss.
“Applied to a population doing an exercise training program with high polyphenol intake with blackcurrant would have really important health implications.”
The supplement also led to large-to-moderate reductions in blood pressure, showcasing how the berry can amplify the heart-health benefits of exercise to a clinically-significant degree.
Cook suggested the discovery positions the high-anthocyanin berry extract as a compelling alternative to Ozempic when used with a controlled diet and exercise, but without the dangerous side effects or high cost.
“A high anthocyanin blackcurrant supplement is an affordable, fast-acting intervention that is easy to use, doesn’t require a prescription, is very safe and a valuable tool for weight management. Not only that, it improves insulin responses, cardiovascular health and lowers risk factors associated with Type 2 Diabetes and heart disease.”
Study methodology
Twenty-two self-reported physically active participants (11 women) volunteered for the study. To participate, participants had to be not using any dietary supplements, nonsmokers, not obese (BMI ≤ 30), and free from any metabolic health disorders.
The experimental design has previously been described (Shan & Cook, 2023). A double-blind, PLA-controlled, randomized crossover design was used, with four laboratory visits at the same time in the morning.
At visits one and two, body measurements, VO2max and blood pressure were measured. Participants underwent 60 minutes of moderate treadmill exercise during moderate-intensity exercise, during which their energy metabolism (fat and carbohydrate use) were measured. Blood pressure responses were measured at rest in the two hours following the treadmill test.
For six days prior to Visits three and four, participants consumed either NZBC (CurraNZ, Health Currancy Ltd.) or PLA (microcrystalline cellulose M102) from two 300-mg identical size, shape, and color capsules..
Two hours following their final dose, participants underwent the same tests as at visits one and two.
90% of the group displayed improvements, with an average group increase of 28%.
Women with the poorest rates of fat burning exhibited the highest response but fat burning effects were not influenced by an individuals’ fitness status.
Considering the greater effect in women with higher body fat, the researchers suggested the berry’s mechanisms of action may be increasing fat transporters into muscle, where fat is metabolized for energy. Women have a higher number of transporters and are more efficient at metabolizing fat than men.
These values are comparable to what a doctor would seek to achieve
Dr Matthew Cook, lead researcher
Speaking about the post-exercise blood pressure responses, Cook added: “We observed that blackcurrant further decreased resting blood pressure values by up to 11% in the two hours after exercise.
“Blood pressure is the pressure that our blood puts on our arteries. We need a certain amount to keep blood flowing, however, if it is too high it can cause health problems.
“Every 5mmHG reduction in systolic blood pressure is equivalent to lowering the risk of cardiovascular events by 10% in adults over 60, however in the present study we saw reductions of up to 12mmHG – or 11%, in young healthy males and females.
“These values are comparable to what a doctor would seek to achieve through prescribing blood pressure medications to their patients. This is really meaningful after just one week on blackcurrant – a fantastic finding.”
Cook noted it would be worth repeating the study and extending the testing window, because post-exercise hypotension can occur for 12-24 hours before returning to baseline.
“There is no question blackcurrant anthocyanins can deliver meaningful physiological health benefits and should be implemented as a daily dietary strategy for life – particularly for those at risk,” added Cook.
“It’s clear that as a population, we don’t exercise enough, or consume enough fruits and vegetables containing these high-value phytochemicals and nutrients. Consuming a nutritional supplement like blackcurrant extract shows that within a short space of time, high doses of anthocyanin can deliver measurable, repeatable benefits that can modify health outcomes.”
International Journal of Sport Nutrition and Exercise Metabolism, 2025, 35, 150-161; “Effects of New Zealand Black Currant Extract on Exercising Substrate Utilization and Postexercise Blood Pressure in Men and Women.” https://doi.org/10.1123/ijsnem.2024-0108; Authors: Cook, M.D., Shan,Y., and Willems, M.E.T.,
