Body Weight and Survival: Recent Trends in the US

Yan Yu, University of Wisconsin at Madison

Continued mortality improvement in the last decades has been accompanied by a large increase in body weight. Today, the majority of the US population is considered overweight or obese, and it has been suggested that if the current trend in body weight continues, the continuing rise in life expectancy would stop. Empirical evidence, however, is limited. Using data from the Second and Third National Health and Nutrition Examination Survey (respective baseline at 1976-80 and 1988-92), this study will accomplish two tasks. First, it examines whether the weight/mortality associations have varied over time. Second, it estimates life expectancy at age 20 for the two periods, and quantifies the respective roles in expectancy changes of a changing population weight distribution, and changing weight/mortality associations, using a standard decomposition procedure. All estimates are standardized by a standard smoking distribution to account for well-documented changes in smoking behavior.