Semaglutide extended the median lifespan of older female mice by nearly 100 days, the National Institutes of Health reported Wednesday. The animal study evaluated whether the GLP-1 agonist could slow physiological aging in healthy older subjects rather than simply manage metabolic disease.
Researchers at the University of California, Berkeley administered semaglutide to 20-month-old female mice for three months. Compared with untreated controls, the treated animals exhibited improved muscle and cognitive performance. Gene expression profiling showed reductions in hallmarks of natural aging, including lower inflammation and preserved regenerative capacity. Mice given semaglutide until the end of life survived nearly 100 days longer on median than control animals.
Danica Chen, corresponding author and professor of metabolic biology and nutrition at UC Berkeley, tested semaglutide against dietary restriction over five months. Her team compared mice given semaglutide with a group fed a 24% calorie-restricted diet matching the drug-treated animals' intake. Semaglutide-treated mice surpassed baseline marks in exploratory behavior, spatial memory, and blood-sugar maintenance, outperforming the calorie-restricted cohort.
Treated mice maintained largely stable metabolic rates, whereas the calorie-restricted group showed a distinct metabolic slowdown. Chen noted that these differences indicate GLP-1 drugs may engage biological pathways independent of calorie restriction, presenting a potential route for longevity-focused interventions. Rafael de Cabo, a senior investigator at the National Institute on Aging who authored an accompanying commentary, noted that if GLP-1 agonists slow aging itself, broad clinical benefits across multiple chronic diseases would follow.
Federal health officials stressed that the findings do not guarantee immediate translation to human longevity. Evaluating human efficacy will require clinical trials, including post-hoc reviews such as the SLIM LIVER analysis, with future work potentially assessing GLP-1 treatments in healthy older adults.
The study, led by Yufan Feng, was published September 2, 2026, in Nature and supported by National Institute on Aging grants R01AG063404, R01AG063389, and R01AG082105.
