What the trial measured
An analysis led by Mass General Brigham investigators found that daily multivitamin supplementation over two years was associated with slowing of biological aging as measured by DNA methylation age (DNAmAge). This is one of the first long-duration randomized controlled trials to use epigenetic clocks as a primary endpoint for a common supplement.
What DNA methylation age means
DNA methylation age, also called epigenetic age or biological age, is calculated by measuring methylation patterns at specific sites on your DNA. These patterns change predictably with age. An epigenetic clock like DNAmAge, GrimAge, or DunedinPACE estimates how quickly your cells are aging compared to your chronological age.
A slower epigenetic age means your cells look younger than your birth certificate says. Whether that translates to living longer or avoiding disease is still being studied. Epigenetic clocks are promising biomarkers but are not yet validated surrogate endpoints for clinical outcomes.
This is one of the first long-duration RCTs to use epigenetic clocks as a primary endpoint for a supplement available at any pharmacy.
Why this matters for multivitamins
Multivitamins are the most widely used supplement category, and most prior evidence has been negative or neutral for hard clinical endpoints like heart attacks, cancer, or mortality. A 2022 USPSTF review found insufficient evidence to recommend multivitamins for chronic disease prevention. If multivitamins slow biological aging even without preventing specific diseases, it would represent a new kind of evidence: a mechanistic effect rather than a clinical outcome.
What we don't know
- Effect size was not specified in the source material.
- Which clock was used (DNAmAge, GrimAge, DunedinPACE, PhenoAge) was not specified.
- Peer-reviewed publication has not appeared at time of writing.
- Clinical outcomes (disease, mortality) were not the endpoint.
What this means for you
If you already take a multivitamin, this is encouraging news but not a reason to change your regimen. If you don't take one, this is not sufficient evidence to start. A 2-year epigenetic clock effect is a biological signal, not a health outcome. The cheapest supplement in your cabinet may be doing something measurable, but we don't yet know if that measurement predicts anything that matters.