Activates AMPK, lowers hepatic glucose production, improves insulin sensitivity. Strong observational data for reduced cancer incidence and all-cause mortality. The most-studied 'longevity drug' outside lab models.
Dose: 500-2000mg daily, with food. Extended-release is tolerated better.
Caveats: GI side effects in first weeks. B12 depletion long-term. Supplement. May blunt training adaptations slightly. Discontinue before contrast imaging.