National Geographic, September 2026

Two hundred years ago, you were lucky if you weren’t taken out by a disease or accident before you turned 20. Today, thanks to numerous medical advances, people live about 80 years, longer than at any other point in human history. That incredible increase in lifespan has led to a new problem: people live long enough to die from the process of aging itself—cancer, heart disease, and more. But what if we could fix that, too? For the last two decades, researchers have chased this grail, and Li...