Daily multivitamin-mineral supplementation in older adults reduces cognitive aging by 2–3 years, as measured by improvements in global cognition, episodic memory, and immediate verbal memory, independent of assessment modality.

Study: Effect of multivitamin-mineral supplementation versus placebo on cognitive function: Results from the clinic sub-cohort of the COSMOS randomized clinical trial and meta-analysis of three cognitive studies within COSMOS.

Taking a daily multivitamin for two years helped older adults think a little better—like their brains were two years younger—especially in memory tasks. The study found this effect was real and not just by chance.

Study: Impact of Multivitamin-Mineral and Cocoa Extract on Incidence of Mild Cognitive Impairment and Dementia: Results from the Cocoa Supplement and Multivitamin Outcomes Study for the Mind COSMOS-Mind

Taking a daily multivitamin didn't stop older people from developing memory problems, but those who took it and still had memory issues declined more slowly than those who didn't. So it helped slow down brain aging, even if it didn't prevent it completely.

Study: Effect of multivitamin‐mineral supplementation on change in cognitive function in the COSMOS Clinical subcohort and meta‐analysis of COSMOS cognition studies

Taking a daily multivitamin helped older adults remember things a little better over two years, and their overall thinking may have improved too. This suggests multivitamins might slow down memory decline, like giving the brain a small boost.