Caloric restriction and human longevity: what can we learn from the Okinawans?

Caloric (or dietary) restriction (CR) extends lifespan and lowers risk for age associated diseases in a phylogenetically diverse group of species. Whether prolonged CR increases average or maximum lifespan or promotes a more youthful physiology in humans at advanced ages is not yet known. However, available epidemiological evidence indicates that CR may already have contributed to an extension of average and maximum life span in one human population and appears to have lowered risk for age associated chronic diseases in other human populations. We review the human studies in the context of a special human population, older Okinawans, who appear to have undergone a mild form of prolonged CR for about half their adult lives.