Body-Mass Index and Mortality in a Prospective Cohort of U.S. Adults

The relation between body weight and mortality remains controversial. Important unresolved questions concern the shape of the curve relating the two variables; the optimal weight for longevity; whether the optimal weight varies according to age, race, or sex; and whether the increased death rates often observed among very lean people are causal or an artifact of leanness due to smoking or concurrent illness. Debate about the potential hazards of excessive leanness has received disproportionate attention in a culture in which obesity is far more prevalent. Much of the vast literature examining the relation between body weight and mortality 1 – 16 supports . . .