Boysenberry juice and after-meal energy use in healthy adults
What it found
In 19 healthy adults, drinking boysenberry juice daily for four weeks did not change after-meal energy expenditure or brown fat activity, but it did increase fat burning after a meal.
The study was small and the authors say it was not powerful enough to be sure about the energy expenditure result.
What they found
Studies in people
After-meal energy use
There was no significant difference in diet-induced thermogenesis, measured as the rise in energy expenditure after a meal, between the boysenberry juice and placebo groups.
Brown fat activity
Skin temperature in the brown fat region above the collarbone did not differ significantly between the boysenberry juice and placebo groups after the meal.
Fat burning
Post-meal fat oxidation was significantly higher after boysenberry juice than after placebo, with an estimated increase of 5.60 mg/min.
Other metabolism measures
Carbohydrate oxidation, oxygen consumption, and respiratory quotient did not differ significantly between the boysenberry juice and placebo groups.
Appetite and warmth
Appetite, cold sensation, and hand skin temperature did not differ significantly between the boysenberry juice and placebo groups.
Side effects
No significant health harms or unintended effects were observed in any participants during the study.
What the authors conclude
“These results suggest that continuous consumption of BoyJ may shift energy utilization toward fat oxidation and promote fat metabolism.”
Also in their conclusions
- They conclude that boysenberry juice intake did not significantly affect diet-induced thermogenesis or brown fat thermogenesis, but did significantly increase post-meal fat oxidation.
- They say the study was underpowered to draw definitive conclusions about diet-induced thermogenesis and recommend larger studies to confirm the fat oxidation finding.
- They note that it is unclear whether these effects would benefit people with metabolic syndrome, and that future studies in that group are needed.
How it was done
The authors wanted to test whether boysenberry anthocyanins could boost diet-induced thermogenesis by activating brown fat, based on earlier mouse studies and a small human trial suggesting cold-related brown fat activation.
They ran a randomised, double-blind crossover trial in 22 healthy men and women aged 20 or older with a BMI between 18.5 and 25.0. Participants drank 100 ml of boysenberry juice containing 61 mg of boysenberry anthocyanins or a placebo daily for four weeks, with a four-week washout between the two periods. Three people withdrew, so 19 were analysed.
What it can’t tell you
- The study was small and the authors say it was underpowered, so the lack of effect on energy expenditure may be inconclusive.
- The authors cannot rule out that the difference in fat oxidation occurred by chance because many secondary outcomes were tested.
- The trial was in healthy adults, so it cannot show whether the effects would be beneficial for people with metabolic syndrome.
Who paid
- Conflicts
- R.F., S.K., and D.M. are affiliated with Bourbon Corporation as researchers. BoyJ and placebo were supplied by Bourbon Corporation for the study. This study was conducted with joint research funds provided by Bourbon Corporation. Bourbon Corporation and Juntendo University have established a collaborative research program funded by Bourbon Corporation, and the program is organized by T.M. The other authors have no conflicts of interest to disclose.
- Authors work at
- Advanced Research Institutes, Japan; Juntendo University Graduate School of Medicine, Japan; Niigata University, Japan
The paper
- Title
- Effects of boysenberry on postprandial energy metabolism in healthy adults: A randomized controlled crossover trial
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Licence
- CC BY. Words in quotation marks are the authors’; the rest is our summary.
- Cite
- Furuuchi R, Kato S, Maejima D, Amano T, Shimizu I, Minamino T (2025). Effects of boysenberry on postprandial energy metabolism in healthy adults: A randomized controlled crossover trial. PloS one. doi:10.1371/journal.pone.0330683Free full textPubMed 40844985DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error