Brain health supplements are booming. Here’s what one longevity expert takes.

 https://www.washingtonpost.com/health/2026/05/07/brain-supplements-longevity/

Only one has been shown in clinical trials to slow cognitive aging, by about two years. This is what the science says about which supplements work.

About 1 in 5 adults over age 50 use vitamins or supplements specifically to try to boost brain functions like memory, attention or focus, according to a 2021 AARP survey, the most recent update. The global market for nutritional supplements was estimated at $517.1 billion in 2025 and projected to be $862.5 billion by 2033, according to Grand View Research.

As more interest and money flow into the space, more serious human research is beginning to take shape. The findings, however, remain modest and uneven.

3. Multivitamin One of the more convincing findings to date about supplements comes from the cognitive substudies of the Harvard-led COSMOS trial, which involved over 2,200 participants followed over roughly two to three years. A paper published in 2024 in the American Journal of Clinical Nutrition found that adults over 60 who took a daily multivitamin scored modestly better on tests of episodic memory than those given a placebo — a gap researchers say amounts to about two years of cognitive aging