Forget those studies of long-lived Italian shepherds and Greek fishermen. It's not fresh air or exercise or a simple whole-foods diet that causes certain people to live past 100, a new study shows. Instead, it's a set of genetic mutations thought to interfere with normal cell growth and thus slow aging.
Dr. Nir Barzilai, director of the Institute for Aging Research at Albert Einstein College of Medicine in New York, found the mutations exclusively among centenarians. They affect sensitivity to insulin growth factor 1, which is crucial to children's growth and contributes to regeneration throughout adulthood.
Earlier studies had shown that mice lacking one copy of the IGF-1 gene live 26 percent longer than normal, on average, and damping down that metabolic pathway extended the lifespan of yeasts, worms, and flies.