Good for your arteries, but not as clear for cognition and mood
STUDY: He Y et al, Nutrition Research 2026;149:162–177
STUDY TYPE: Systematic review and meta-analysis
FUNDING: Analysis was government (China) funded, but many studies were funded by the blueberry industry
Background
Blueberries are rich in antiinflammatory anthocyanins that give it their blue (ok, purple) hue and are thought to benefit cognition and vascular health. This review concludes they do one of those.
The Study
This meta-analysis pooled 14 RCTs involving 632 healthy participants aged 7 to 80 years. They compared blueberry supplementation in various forms — fresh, freeze-dried, or extract, usually against a similar-looking placebo.
Blueberry supplementation helped arteries dilate more flexibly (flow-mediated dilation, FMD) by 1.11%. That’s a modest but potentially meaningful change, as each 1% rise in FMD is associated with a 13% reduction in cardiovascular events like heart attack and stroke.
Cognitive and mood outcomes trended positively, but there was too much statistical blur in the pooled results to call it (ie, the confidence limits crossed the zero threshold).
But for blueberry enthusiasts, the race is not over. It’s difficult to show an effect in healthy people. When this data is limited to older adults with some cognitive decline, as other other analyses have done, we see benefits in episodic memory, cognitive decline, language, and working memory (the n-back test). Higher doses and longer durations of use predict greater improvement. Across these studies, their mood benefits are suggestive but unproven.
Other polyphenols, like citrus, berries, tea, and dark chocolate, have similar effects.
Practice Implications
- The young and healthy aren’t likely to feel smarter on blueberries, but their vascular health will benefit builds over time.
- Older adults with cognitive problems may see a small improvement in cognition with 1/2-1 cup of berries a day as early as one month, and that improvement grows with time.
— Chris Aiken, MD
Director, Psych Partners
Editor in Chief, Carlat Psychiatry Report
