A daily multivitamin may modestly slow biological aging, according to new research published in Nature Medicine. Scientists analyzing data from the COSMOS clinical trial found that older adults who took a daily multivitamin showed slower changes in certain epigenetic “aging clocks,” which measure biological aging through DNA markers rather than chronological age.
Researchers examined blood samples from 958 participants with an average age of 70 who were part of the large randomized COSMOS trial. Over two years, participants who took a standard multivitamin showed slower progression in two biological aging markers compared with those who took a placebo. The difference translated to roughly 2.7 to 5.1 months of slower biological aging over the study period.
The benefits appeared strongest in participants who showed signs of accelerated biological aging at the start of the trial. Researchers caution that the field is still developing and more studies are needed to determine whether slowing these epigenetic markers will ultimately translate into longer or healthier lives. Experts say multivitamins may help fill nutrient gaps, but maintaining a healthy lifestyle — including balanced nutrition, regular activity and adequate sleep — remains key for healthy aging.
SOURCE:
Medical News Today, March 10, 2026