TL;DR
The drugs millions of people already take to lose weight may also be slowing the body's aging clock. Novo Nordisk says people on semaglutide read about two to four years younger than people on placebo on a heart-protein aging test, across 10,052 trial participants. If that holds, the first "anti-aging" medicine could be one already on pharmacy shelves. But the measuring stick itself is unproven: more than 100 aging clocks exist, they disagree wildly, and no regulator accepts any of them. Whoever proves a clock actually predicts a longer, healthier life will shorten every longevity trial that follows from decades to months. A federal project owes its first answer by August 2027.
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