Data from insurance databases and large, prospective cohorts, such as findings from the Framingham and National Health and Nutrition Examination Survey (NHANES) studies, clearly indicate that obesity is associated with a substantial increase in morbidity and mortality rates.

The adverse consequences of obesity may be attributed in part to comorbidities, but results from several observational studies detailed by the Expert Panel on the Identification, Evaluation, and Treatment of Overweight Adults, as well as results from reports by Allison, Bray, and others, exhaustively show that obesity on its own is associated with increased cardiovascular morbidity and mortality and greater all-cause mortality.