What adult weight best advances health, minimizes the risk of chronic disease, and promotes longevity? This question has engaged the interest of the public, health care professionals, and a wide range of clinical investigators. The consequences of answering this question have profound health, social, and economic implications for individuals, communities, and the population as a whole.
A Metropolitan Life Insurance Company (MLIC) statistician revealed an association between longevity and body weight in 1942. Lifespan was longest when body weight was maintained at the same level as 25-year-old adults with similar height and frame size.1 The initial 1942 MLIC ideal body weight tables were later revised to desirable weight tables in 1959 and again in 1983 to height and weight tables. Obesity was considered present when a person's weight exceeded his or her desirable weight by 20%.