Daily multivitamin shifts epigenetic ageing clocks in older adults

A two-year randomized trial of 958 older adults found that a daily multivitamin was associated with a small slowing in some DNA-methylation “age clocks” — roughly four months’ worth of reduced biological ageing over the study period, according to The Guardian’s summary of the Nature Medicine paper. Participants, with an average age around 70, were assigned to combinations of multivitamin, cocoa extract, both, or placebo, and provided blood samples at baseline, year one, and year two.

The headline result rests on a specific measurement choice: epigenetic clocks. These clocks estimate “biological age” by reading patterns of DNA methylation that correlate with ageing and, in some models, mortality risk. In the trial, the multivitamin signal appeared clearly in two of the five clocks analysed — particularly those marketed as being closer to mortality prediction — while cocoa extract showed no effect. That split matters because it frames the finding less as “ageing slowed” and more as “two algorithms moved in the desired direction.” The Independent notes that the effect size is small and not consistent across all measures, while outside experts caution that methylation clocks are only one layer of ageing biology, alongside processes like DNA damage, protein dysfunction, and cellular signalling.

The study also points toward a mechanism that is both plausible and commercially inconvenient: benefits may be concentrated among people who start with poorer nutritional status. According to The Guardian, participants who were “ageing faster” at baseline appeared to show larger changes, which the authors suggest could reflect greater nutritional deficits. That interpretation would make multivitamins less of a universal longevity hack and more of a patch for uneven diets — a problem with clear socioeconomic and clinical screening angles.

What the study does not provide is the outcome that would settle the question for most people: fewer heart attacks, fewer fractures, delayed disability, or longer life. A large 2024 analysis previously reported no longevity benefit from daily multivitamins and hinted at possible harm, a reminder that biomarker movement can be easier to demonstrate than meaningful endpoints. Yet biomarkers are precisely what can be productised: they turn “ageing” into a number that can be sold, retested, and improved with a stack of supplements — long before any health system would pay for proof.

In this trial, the multivitamins were supplied via industry involvement (Mars Edge is cited by The Guardian; Centrum is noted by Business Insider), while the authors and commentators emphasise uncertainty about who benefits and how. The result is a familiar gap: a measurable shift in a proxy metric, paired with a market ready to treat that proxy as the product.

The study’s most concrete claim is not that people will live longer, but that two methylation clocks moved by the equivalent of a few months over two years — a number small enough to fit neatly inside the error bars of everyday life.