An analysis of 51 longitudinal studies and more than 110 DNA methylation biomarkers found that three classes of medication — the diabetes drug metformin, the weight-loss and diabetes drug semaglutide, and anti-inflammatory anti-TNF treatments — were associated with the largest drops in measures of biological age, across 16 epigenetic clocks, Asharq Al-Awsat reported.
The findings, published in Nature Medicine and reported by Medical News Today, center on “epigenetic clocks” — tools that track chemical changes, called DNA methylation, that accumulate on DNA over time and are used to estimate how old the body is physiologically, rather than how many years a person has lived.
What the researchers measured
Biological age reflects the physiological state of the body and how far it has progressed in aging, rather than the number of years since birth. By measuring DNA methylation patterns, epigenetic clocks let researchers estimate that biological age and watch how it shifts in response to diet, exercise, drugs, and supplements.
The researchers examined data from 51 longitudinal studies of interventions aimed at slowing aging, testing the effect of each on more than 110 biomarkers tied to DNA methylation.
Drugs outpaced diets in the measured effect
Healthy diets — including the Mediterranean diet and low-carbohydrate or low-fat regimens — combined with regular exercise were associated with reduced epigenetic aging markers. But the biggest effect appeared with medication.
Metformin, a standard treatment for type 2 diabetes; semaglutide, a GLP-1 receptor agonist used for diabetes and weight management; and anti-TNF therapies, used to control inflammation, were each linked to a notable decline in age markers across the 16 epigenetic clocks included in the analysis.
Supplements showed no consistent anti-aging signal
The researchers found no strong, consistent evidence that dietary supplements produce anti-aging effects. Raghav Sehgal, a co-author of the study at Yale School of Medicine, said that does not make supplements useless — they may matter for people with nutritional deficiencies or specific medical needs — but many claims that they slow aging still run ahead of the available scientific evidence.
Why the results do not prove longer life
The researchers cautioned that changes in DNA methylation markers do not by themselves prove that an intervention extends lifespan or preserves physical and cognitive abilities. Sehgal said the markers allow scientists to track biological changes over months or years, instead of waiting decades to see whether an intervention reduces disease or death risk. Long-term studies are still needed to confirm that these changes translate into better health and quality of life.
Unlushler warned against reading the results as a recommendation for healthy people to take metformin, semaglutide, or anti-inflammatory drugs to slow aging. Some of the studies involved people with specific health conditions, she noted, so the recorded changes may reflect improvement in the underlying disease, inflammation, or metabolic health rather than a direct effect on the aging process itself.
For now, she said, epigenetic clocks should be treated as promising research tools, not final medical measures of an individual’s health.
What the evidence supports today
Sehgal said no single intervention has been proven to comprehensively slow aging in humans. The measures with the strongest evidence remain basic daily habits: not smoking, exercising regularly, eating a balanced diet, getting enough sleep, and controlling blood pressure, cholesterol, and diabetes.
Unlushler agreed, emphasizing a mix of aerobic and resistance exercise, a Mediterranean-style diet, maintaining a healthy weight, limiting alcohol, keeping regular sleep schedules, and properly managing chronic conditions such as high blood pressure, high cholesterol, and diabetes — all of which support metabolic, cardiovascular, and brain health over the long term.
The debate sits inside a growing longevity industry that markets supplements, genetic tests, biological-age testing, and experimental treatments as ways to restore youth, Al Jazeera reported. That commercial push contrasts with a separate large U.S. study published in PEOPLE, which found that at age 40 the life-expectancy gap between the richest 1% and poorest 1% of Americans was about 14.6 years for men and 10.1 years for women — a reminder that factors like education, health behavior, environment, and access to care, not just new drugs, shape how long and how well people live.
Clocks track biological aging through DNA changes
What are epigenetic clocks? They are tools that measure chemical changes — DNA methylation — that accumulate on DNA over time, allowing researchers to estimate a person’s biological age rather than counting years since birth.
Which interventions showed the biggest effect? Metformin, semaglutide, and anti-TNF anti-inflammatory treatments were associated with the largest average reduction in age markers across 16 epigenetic clocks in the analysis of 51 studies.
Do these findings mean the drugs will extend life? No. The researchers stress that changes in methylation markers do not prove longer life or preserved function; long-term studies are still needed to confirm real health outcomes.
Should healthy people take these drugs to slow aging? The study authors explicitly warned against that interpretation, noting that some trials involved people with existing health conditions, so the changes may reflect treatment of disease rather than a direct anti-aging effect.
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