A pooled analysis of 51 studies published in Nature Medicine found that healthy diets, regular exercise and three classes of prescription drugs reduced epigenetic aging measures, while over-the-counter supplements produced limited and inconsistent evidence. Researchers ran more than 3,000 samples through the same panel of 16 epigenetic clocks plus 94 additional DNA methylation biomarkers.

Epigenetic clocks estimate biological age by reading chemical tags called methyl groups attached to DNA in a blood sample. Those patterns shift over a lifetime, which makes them a faster readout than waiting decades to count illnesses and deaths.

Why the scale matters

Most longevity headlines come from one trial measured against one clock. Here dozens of studies went through an identical biomarker panel, which is what lets a reader put a diet trial and a drug trial on the same axis at all.

What moved the needle

Two lifestyle categories reduced epigenetic aging in the pooled data: healthy eating patterns, including Mediterranean, low-carbohydrate and low-fat diets, and regular exercise. Neither is a surprise, but a consistent signal across a standardized panel is a different thing from scattered single-study results.

The largest average effects came from medications. Metformin, semaglutide, and anti-TNF therapies used to control inflammation each significantly decreased measured age across all 16 clocks.

The reading the authors want to block

Sebnem Unluisler, a genetic engineer and chief longevity officer at the London Regenerative Institute who was not involved in the study, said the drug findings are scientifically interesting but "should not be interpreted as evidence that these medications should be taken by healthy people." Some studies involved specific patient populations, she noted, so the changes may partly reflect improvements in underlying disease, inflammation or metabolic health. The Yale announcement adds that the biomarkers moved more in people with diseases than in healthy volunteers.

Limitations

Corresponding author Raghav Sehgal, of the Yale University School of Medicine, told Medical News Today that biomarkers are not a replacement for long-term studies, and that researchers still need to show these changes translate into people staying healthier, functioning better or living longer.

Bottom line

Sehgal said the evidence for supplements was limited and inconsistent, while stressing that is not the same as useless. His summary was that no single intervention is yet proven to broadly slow aging in humans.