The Digester

Daily multivitamin slows markers of biological ageing

Mar 10th 2026

A two-year randomized trial of 958 older adults found that taking a daily multivitamin modestly slowed certain epigenetic ageing clocks by about four months, with stronger effects in those showing accelerated biological ageing, though clinical impacts remain unproven.

  • Randomized controlled COSMOS trial of 958 adults published in Nature Medicine followed participants for two years with blood samples at baseline, 12 months and 24 months.
  • Daily multivitamin use was associated with about a four month reduction in epigenetic ageing markers compared with placebo over two years.
  • Researchers measured five DNA methylation clocks and found significant slowing in two clocks that are linked to mortality risk.
  • The effect was larger in people whose biological age was already older than their chronological age.
  • The observed benefit is small and has not been tied to clinical outcomes like disease or lifespan yet

Sources

nature.com