In a meta-analysis of 5,000 participants, including more than 500 who underwent in-person assessments over two years, multivitamins showed benefits for memory and global cognition.
The COcoa Supplement and Multivitamin Outcomes Study (COSMOS) is a large-scale, nationwide, randomized trial rigorously testing cocoa extract and multivitamin supplements directed by researchers at Mass General Brigham. Two previously published studies of cognition in COSMOS suggested a positive effect for a daily multivitamin. COSMOS researchers now report the results of a third study of cognition in COSMOS, which focused on participants who underwent in-person assessments, together with the results of a combined analysis from the three separate studies. The results from this latest report confirm consistent and statistically significant benefits of a daily multivitamin versus placebo for both memory and global cognition. Results are published in The American Journal of Clinical Nutrition.
In the in-clinic study the researchers administered detailed, in-person cognitive assessments among 573 participants in the subset of COSMOS known as COSMOS-Clinic. Within COSMOS, two previous studies had tested multivitamin supplementation on cognition using telephone-based cognitive assessments (COSMOS-MIND) and online web-based cognitive assessments (COSMOS-Web). In their prespecified analyses of data from COSMOS-Clinic, investigators observed a modest benefit for the multivitamin, compared to placebo, on global cognition over two years. There was a statistically significant benefit of multivitamin supplementation for change in episodic memory, but not in executive function/attention.
The team also conducted a meta-analysis based on the three separate studies, with non-overlapping COSMOS participants (ranging 2-3 years in treatment duration), which showed strong evidence of benefits for both global cognition and episodic memory. The authors estimate that the daily multivitamin slowed global cognitive aging by the equivalent of two years compared to placebo.