Epidemiology, trends, and morbidities of obesity and the metabolic syndrome.

Obesity has been described as an epidemic because of the rapid increase in the number of overweight and obese individuals over the past 20 yr. This increasing prevalence of obesity is a worldwide phenomenon affecting both children and adults. The metabolic syndrome is a constellation of central adiposity, impaired fasting glucose, elevated blood pressure, and dyslipidemia (high triglyceride and low HDL cholesterol). When three of these five criteria are present, the risk of cardiovascular disease and diabetes is increased 1.5- to 2-fold. As body weight, expressed as the BMI, rises, there are a number of other diseases that are associated with it. First, life span is shortened and the risk of sudden death increases. Second, the risk of diabetes, gall bladder disease, hypertension, heart disease, osteoarthritis, sleep apnea, and certain forms of cancer also increase.