In a clinic where blood samples were collected from 958 older adults enrolled in a randomized trial, the question was simple and intimate: can a daily pill change the way our DNA signals the passage of time? The COSMOS prespecified ancillary study placed multivitamins at the center of that question, using five DNA methylation measures to test whether a once-daily multivitamin–multimineral regimen could slow biological aging.
What did the COSMOS trial test?
Researchers in the COcoa Supplement and Multivitamin Outcomes Study (COSMOS) measured five epigenetic clocks—PCHannum, PCHorvath, PCPhenoAge, PCGrimAge and DunedinPACE—among 958 participants (482 women and 476 men). The interventions were a daily multivitamin–multimineral supplement identified as Centrum Silver and a cocoa extract providing 500 mg of cocoa flavanols per day, including 80 mg (−)-epicatechin. The trial compared each active intervention with placebo over two years and analyzed yearly change in the epigenetic clocks using DNA methylation from blood or saliva.
Do Multivitamins slow biological aging?
Short answer: the study found small, statistically significant slowing on two second-generation epigenetic clocks. Compared with placebo, daily multivitamin–multimineral supplementation produced a between-group difference in yearly change of −0. 113 years for PCGrimAge (95% confidence interval −0. 205 to −0. 020; P = 0. 017) and −0. 214 years for PCPhenoAge (95% confidence interval −0. 410 to −0. 019; P = 0. 032). The multivitamin effect on PCGrimAge was larger among participants with accelerated biological aging at baseline (−0. 236) than among those with normal or decelerated aging (−0. 013), with a statistically significant interaction.
Cocoa extract showed no effect on any of the five epigenetic clocks tested. The authors described the multivitamin findings as statistically significant but small, and they noted that further work is required to determine clinical relevance and whether epigenetic changes explain prior observations that multivitamin supplementation can benefit some age-related conditions.
Howard Sesso, an epidemiologist and associate professor of medicine at Harvard Medical School who served as a lead study author and senior investigator affiliated with Mass General Brigham, said, “This doesn’t mean that everyone should go out and start taking a multivitamin. ” He added, “Rather, this is starting to provide the connecting dots. “
What does this mean for older adults and researchers?
The trial’s results are cautiously framed: they offer an encouraging signal that a broad-based daily supplement may modestly affect epigenetic measures of aging in older adults, particularly those showing evidence of accelerated biological aging at baseline. The investigators emphasize that the observed effects are small in magnitude and that epigenetic clocks are imperfect predictors of clinical outcomes.
Study authors call for larger, longer trials and additional analyses to determine whether the measured changes translate into meaningful improvements in healthspan or reductions in age-related disease. Within COSMOS, investigators continue to build biomarker resources to connect interventions with clinical outcomes and to test mechanisms that could explain observed benefits in inflammation and cognitive measures noted in related analyses.
“A lot of people take a multivitamin without necessarily knowing any benefits from taking it, so the more we can learn about its potential health benefits, the better, ” said Howard Sesso, underscoring both the public interest and the scientific caution surrounding supplementation.
Back in the clinic where samples were drawn, the trial’s modest findings leave a tangible afterimage: a routine, inexpensive pill produced measurable shifts on molecular clocks, but the human meaning of those months shaved from a calculated biological age remains unresolved. The COSMOS team has opened a door; whether stepping through it will change how clinicians or individuals act will depend on the larger trials and clinical endpoints that follow.
