[Aging society and successful aging].

In rapidly aging society like Japan, it is imperative for aged persons to accomplish what we call 'successful aging'. The components of successful aging are (1) high physical function with low risk of disease, (2) good cognitive function and (3) high level of engagement to life and society. Ample evidence obtained from medical research suggests how age-associated diseases can be prevented and how high physical activity can be maintained in aged persons. More studies are required, however, to know how deterioration of cognitive function can be prevented. Those who participate in work or in social activities are less likely to show physical or mental decline. Interdisciplinary researches are required to find ways for achieving successful aging in Japan.