Daily multivitamin linked to slower biological ageing in epigenetic clocks, Mass General Brigham finds

Many people swallow a multivitamin every day, trusting it could support health in later life. Yet demonstrating a clear advantage has long been challenging.

Researchers at Mass General Brigham have now reported evidence that this familiar supplement could be linked to biological ageing.

In a trial of older adults, those assigned to a daily multivitamin showed a small slowing in the pace of certain “epigenetic clocks” - blood-based indicators used to estimate how quickly the body is ageing.

Across two years, the gap amounted to roughly four months less biological ageing than in the placebo group.

The findings do not imply vitamins halt ageing. Instead, they offer an uncommon signal that an everyday nutritional supplement might gently steer internal ageing processes in a healthier direction.

The body’s internal ageing clock

To assess ageing, the researchers used epigenetic clocks, which are blood tests scientists apply to estimate the rate at which the body is ageing.

These clocks work by detecting tiny chemical markers attached to DNA. As cells experience time, stress and damage, these markers can shift and influence how genes behave.

More recent versions of the clocks do more than approximate age. They are intended to reflect risks connected with disease and survival.

For that reason, even modest movements in these measures can draw interest - particularly when the intervention is as commonplace as taking a daily multivitamin.

Testing multivitamins in an ageing trial

This investigation was nested within the wider Cocoa Supplement and Multivitamin Outcomes Study (COSMOS). For this analysis, the team monitored 958 healthy adults, with an average age of about 70.

Volunteers were randomly allocated into four groups, allowing the researchers to disentangle the effects of a daily multivitamin from those of cocoa extract.

Over a two-year period, participants provided blood samples at multiple follow-up visits. That approach let the scientists observe changes in ageing markers over time, rather than relying on a single measurement.

Because assignment was randomised, the study design offered a far more rigorous test of multivitamin effects than typical day-to-day supplement use.

A modest ageing slowdown

By year two, all five ageing clocks had shifted slightly in the same direction, although only two moved enough to be particularly notable.

Those two clocks are strongly tied to the risk of death from age-related disease, which made the change more consequential.

Looking across the full two years, the difference worked out at about four months less biological ageing for the multivitamin group compared with those taking a placebo.

Even so, participants did not become biologically younger, and the research does not assert that the supplement increases lifespan.

Who benefited the most

The largest apparent benefit was seen in participants whose biology already seemed older than their chronological age.

Within this group, the most pronounced shifts again appeared on those same measures, suggesting the effect was strongest where ageing looked to be progressing fastest.

In a smaller subset, lower nutrient indicators were associated with faster ageing, raising the possibility that correcting subtle nutritional shortfalls could reduce cellular strain.

That explanation remains speculative and would require stronger evidence, and it is only one potential reason the benefit was not uniform.

Cocoa offered no ageing shift

In contrast, the cocoa extract group did not show a convincing slowing of any of the five ageing clocks. This comparison mattered because both supplements were evaluated within the same trial and against the same underlying variability.

One straightforward interpretation is that different interventions may affect different aspects of ageing, while these blood markers capture only part of the picture.

As a result, the multivitamin finding appeared narrower - but also more targeted - than a broad claim that supplements slow ageing.

Multivitamin benefits beyond ageing

Elsewhere in the COSMOS programme, the multivitamin has shown suggestions of benefit in other areas. A previous analysis reported improvements in overall thinking ability, memory and planning after three years of daily use.

However, the main COSMOS trial did not observe reductions in total cancer or cardiovascular disease, although lung cancer was less common among those taking the supplement.

Taken together, these mixed findings imply there may be some advantages, but the overall evidence remains inconclusive.

Small changes, big questions

The clock shifts were small, and three of the five clocks did not change enough to meet the same statistical bar.

The participant pool also had limits: most volunteers were white and all were older adults, so the results may not translate to younger people or to more ethnically diverse groups.

Another recent study reported similarly modest changes in ageing-clock measures with omega-3 supplements, suggesting small shifts of this type may not be unusual.

“There is a lot of interest today in identifying ways to not just live longer, but to live better,” said Dr. Howard Sesso, the study’s lead author.

Testing the multivitamin further

The researchers next want to learn whether the slower clock readings persist once the trial is over. They also aim to examine whether these blood changes could help account for earlier signals of better memory or reduced disease risk.

“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 Dr. Sesso.

This follow-on work is important because people do not take vitamins to improve a laboratory measure - they take them in the hope of ageing well.

At this stage, the data indicate that an inexpensive, familiar pill does not stop ageing, but it may shift two well-regarded blood measures slightly towards a younger profile.

For now, the result looks less like a breakthrough and more like a cautious lead that deserves further testing, rather than a reason to view multivitamins as a cure-all.