A daily multivitamin may modestly slow the biological aging process in older adults, according to research published in the journal Nature Medicine.
A randomized study of 958 older adults found that those who took a daily multivitamin for two years experienced a slowing of “biological aging” by approximately four months.
Researchers observed that while 24 months passed chronologically, the participants’ bodies aged only 20 months at a cellular level. Unlike chronological age, which tracks time since birth, biological age reflects the “wear and tear” on cells and tissues, a metric that varies based on genetics, lifestyle, and medical history.
The research was part of the Cocoa Supplement and Multivitamin Outcomes Study (COSMOS), which tracked healthy men aged 60 and older and women aged 65 and older.
To measure these changes, scientists utilized “epigenetic clocks”—biomarkers that analyze small changes in DNA over time. The slowing of aging was specifically observed through two “second-generation” clocks, known as PCGrimAge and PCPhenoAge, which are used to gauge mortality. While multivitamins showed a benefit, cocoa extract, also tested in the trial, had no effect on biological aging.
While the findings are notable, the study revealed that the benefit was particularly pronounced in individuals who showed signs of accelerated biological aging at the study’s outset, with some seeing double the slowing effect.
Experts described the overall impact as modest, noting that multivitamins are not intended to rejuvenate the body but rather to support health trajectories.
However, the study’s scope was limited by its demographic focus, as participants were primarily healthy and white, leaving questions as to whether these results extend to more diverse populations or those with chronic illnesses. Additionally, the trial received partial funding from Haleon and Mars Inc., although the researchers maintained that these companies were not involved in the design of the study.
“What it means is that your trajectory of health moving forward should stand to benefit,” said Howard Sesso, the study’s senior author and associate director of preventive medicine at Brigham and Women’s Hospital and Harvard Medical School.
Sesso cautioned that the results do not necessarily mean a multivitamin adds four months to a person’s total lifespan and emphasized that the decision to take a multivitamin should always be made in consultation with a healthcare provider.