Supplement analysis backed by scientific evidence · PT

← All supplements
Limited evidenceBrain & cognition

Blueberry Extract

Anthocyanin-rich blueberry preparations show small, inconsistent cognitive benefits, mostly in older adults who already have some decline. The effects are real enough to keep studying but too small and unreliable to promise anyone sharper thinking.

What the science says

  • Cognition in older adults with existing decline Limited evidence

    A 2025 systematic review and meta-analysis with Bayesian post hoc analysis of RCTs in elderly people with prior cognitive decline found benefits that were small and accompanied by substantial uncertainty. Trials typically ran 12-24 weeks with a handful of dozens of participants each, and outcomes varied widely across cognitive domains.

  • Cognition and mood in healthy adults Limited evidence

    A systematic review and mini meta-analysis of human intervention studies found blueberry effects on cognitive health and mood were mixed, with acute improvements in some attention and executive-function tasks and null results in others. Positive findings cluster in children and older adults rather than healthy young or middle-aged people.

  • Vascular function and blood pressure Limited evidence

    Blueberry anthocyanins improve flow-mediated dilation acutely in several small trials, and some chronic studies report reductions in systolic blood pressure of a few mmHg. The vascular data are more mechanistically coherent than the cognitive data but still come from small trials, many industry-supported.

Dosage & safety

Studied doseWhole-food trials used 24-26 g/day of freeze-dried blueberry powder, roughly equivalent to one cup of fresh berries. Extract trials generally used preparations standardized to about 250-500 mg anthocyanins per day, for 12-24 weeks. Eating the berries is a reasonable substitute for the powder.
SafetyVery safe; the common complaints are mild GI upset and loose stools at high powder doses. Concentrated polyphenol extracts theoretically add to the effect of anticoagulants and antiplatelets, so mention them to your clinician if you are on warfarin. Extracts are not equivalent to whole fruit and are frequently under-standardized: look for a stated anthocyanin content rather than a milligram figure for "blueberry." Diabetics should note whole-fruit powders carry real carbohydrate.

Scientific references

Where to buy

View on iHerb

Referral link — this site may earn a commission on purchases.

Related in Brain & cognition