ABSTRACT
This chapter discusses past and future trends in life expectancy and life span, and explores the impact of increased life expectancy on morbidity and disability. Between 1900 and 1940, overall life expectancy increased by over fourteen years while life expectancy for those aged 65 increased by less than one year. The changing pattern of mortality and increasing life expectancy has had, and will continue to have, an important impact on the size and age distribution of the US population. A number of interventions that appear to increase life span in rodents also produce weight loss, and their life-extending properties are probably related to reduced caloric intake. Added years of life resulting from a postponement of severe, debilitating disease certainly would be far better than added years of life resulting from an extension of life in those already seriously ill.
