The prevalence of obesity increased markedly in the United States from the 1960's to the 1980's, and varied by race and gender with particularly high rates of obesity among Black women. Reasons for the ethnic differences in the prevalence of obesity were not understood. This cross-sectional study was performed in conjunction with the 10-year follow-up examination for the Coronary Artery Risk Development in Young Adults (CARDIA) study, an NHLBI-funded longitudinal study of development of risk factors for coronary heart disease (CHD) in young black and white adults.