Daily Multivitamins Show Modest Anti-Aging Signal, Cocoa Flavanols Fall Short

A large 2-year randomized trial from the COSMOS study (Nature Medicine, 2026) found that daily multivitamin–multimineral supplementation produces a small but statistically significant slowing of biological aging, as measured by DNA methylation clocks such as PCGrimAge and PCPhenoAge. The effect was more pronounced in individuals with accelerated aging at baseline, suggesting higher responsiveness in vulnerable populations. In contrast, cocoa flavanol supplementation showed no impact on any epigenetic aging markers despite prior expectations. While the magnitude of benefit with multivitamins was modest, the findings provide controlled evidence that micronutrient repletion may influence aging biology, though its translation into clinical outcomes like longevity or disease reduction remains unclear.

Source : https://www.nature.com/articles/s41591-026-04239-3