Are multivitamins really good for longterm health? (Photo by Fida Olga on Shutterstock)

A pill that tens of millions of Americans already take every morning may do something scientists have long hoped to prove: slow the biological clock ticking inside their cells.

A large randomized clinical trial published inNature Medicinefound that adults who took a daily multivitamin-multimineral supplement for two years showed measurably slower biological aging compared to those who took a placebo. Researchers tracked the effect using epigenetic clocks, molecular tools that read chemical marks on DNA to estimate how fast a person’s body is aging, independent of how many birthdays they’ve had.

The effect was modest, not dramatic. But in a field where mostanti-aging researchinvolves extreme interventions like severe caloric restriction or experimental drugs, the idea that anover-the-counter multivitamincould register a detectable change in the biology of aging is worth taking seriously.

As people age, chemical tags accumulate on their DNA in predictable patterns. Scientists have learned to read those patterns as a kind ofbiological age, one that can differ meaningfully from a person’s actual age. Two 70-year-olds can look quite different at the cellular level. One’s cells may behave like those of a 65-year-old; the other’s may behave more like those of a 75-year-old. Those differences are linked to real health outcomes, includingcognitive decline,cancer risk, and cardiovascular disease.

Researchers focused on two well-validated epigenetic clocks, PCGrimAge and PCPhenoAge, both trained to predict mortality and disease risk rather than simply estimate age. Adults taking a daily multivitamin-multimineral supplement, specificallyCentrum Silver, showed a slower rate of increase on both measures over two years. Over that period, the difference translated to roughly two and a half to five months of reduced biological aging compared to placebo. That’s a small number, but it’s a number produced by a supplement most older Americans can walk into any pharmacy and buy for under $20.

The data held a particularly interesting finding for people who were already aging faster than their chronological age at the start of the study. Among participants whose biological age was running ahead of their actual age, the multivitamin’s effect was considerably stronger than it was in the rest of the group. For those with the most accelerated biological aging at baseline, the slowing effect on PCGrimAge was considerably stronger than it was for participants whose biological age was tracking normally, while those in the normal or decelerated range saw little to no benefit at all.

A pattern in the nutritional data may help explain why. Participants with accelerated biological aging tended to have lower levels of key nutrients likefolateandluteinat baseline, and multivitamin use appeared to raise those levels over time. One reasonable interpretation: when nutritional gaps are quietly driving faster cellular aging, filling them in may ease some of that biological strain. Since COSMOS participants were generally healthy older adults, the benefit could be even more pronounced in populations with poorer diets or greater nutritional deficiencies.

The trial also tested cocoa extract, rich in compounds calledflavanolsthat have shown cardiovascular benefits in other research. Despite earlier lab-based signals that flavanols might influence DNA methylation, the cocoa extract had no meaningful effect on any of the five epigenetic clocks tested. The researchers suggested that its cardiovascular benefits, which have been documented in the broader COSMOS trial, may operate through biological pathways that these particular aging clocks don’t capture.

The findings come from COSMOS, a large randomized, double-blind, placebo-controlled trial that enrolled more than 21,000 adults across the United States. For this specific analysis, 958 participants, women 65 and older and men 60 and older, were randomly selected for DNA methylation testing, with blood samples drawn at the start of the study and at one and two years of follow-up. Their average age was 70, and roughly half were women. Compliance was high throughout, with more than 91 percent of the multivitamin group stilltaking the supplementas directed at the two-year mark.

Source: Drudge Report