Studies of the impact of age on optimal body weight 11This paper was delivered at the 23–25 October 1997 conference “The Determination, Treatment, and Prevention of Obesity,” which was sponsored by the Institute of Nutrition, University of North Carolina at Chapel Hill; Department of Nutrition, School of Public Health and School of Medicine, University of North Carolina at Chapel Hill; and School of Medicine, East Carolina University, in cooperation with the North American Association for the Study of Obesity, the National Institutes of Health, the American Cancer Society, and Eli Lilly & Company.