UC Berkeley Study Shows Semaglutide Extends Median Lifespan in 20-Month-Old Mice by Nearly 100 Days

Researchers administered semaglutide to older female mice and directly compared outcomes against a 24% calorie-restricted group matched for intake. The design included both a three-month functional assessment arm and a lifespan arm continued until death, allowing separation of appetite-suppression effects from other mechanisms. Gene-expression data showed reduced inflammation and improved tissue-repair signatures that exceeded those seen with diet alone. Metabolic rate remained stable in the drug group but declined under calorie restriction, indicating an independent pathway. These results suggest GLP-1 agonists may modulate aging processes beyond simple energy restriction, yet the entire dataset derives from a single mouse strain and sex.