Dietary supplements that boost brain power lack strong evidence Original paper

“Smart drugs” or “nootropics” are essentially dietary supplements that are promoted for brain health and cognitive function. This massive market claims that these supplements benefit cognition in elderly and healthy populations by both preventing decline and boosting performance. Are the claims scientifically sound?

This systematic review identified 9 (out of 54 searched) dietary supplement ingredients with at least 3 published studies (yielding a total of 69 studies) that evaluated cognitive performance benefits.

Bacopa monnieri (7 studies), choline (5 studies), creatine (3 studies), omega−3 fatty acids (10 studies), Ginkgo biloba (16 studies), ginseng (16 studies), Rhodiola rosea (5 studies), tyrosine (4 studies), and valerian root (3 studies) were compared to a placebo at various doses and durations.

Overall, the studies were inconsistent and imprecise with respect to standardization of dietary supplement ingredients, dosage, and duration of use and suffered from various methodological flaws (e.g., small sample sizes, self-reported outcomes). Only 23% of the studies mentioned qualitative/quantitative purity testing of the product’s claimed bioactive ingredients.

Future studies should focus on product standardization, quality, and safety along with more consistent practices for evaluation of cognitive performance benefits.