Spermidine

A polyamine that triggers autophagy — the cellular recycling process linked to longevity. Mouse and human observational data are striking.

Spermidine is a polyamine the body makes, but levels drop with age. It's a powerful inducer of autophagy — the process by which cells break down and recycle damaged proteins and organelles. Autophagy is a key longevity pathway (the only intervention that's reliably extended lifespan in every species tested, from yeast to mice, is caloric restriction — which activates autophagy). Animal studies show spermidine extends lifespan, protects the heart, supports cognition. Human observational data echoes this: higher dietary spermidine intake tracks with lower all-cause mortality. The Madeo lab in Graz has driven much of the recent research.