The obesity epidemic continues without slowing in the United States. In the last report from the National Health and Nutrition Examination Survey (NHANES), the obesity trends across all groups were either unchanged or growing . Despite the focus on obesity prevention and treatment, there has been little impact on this epidemic. Obesity is defined as a body mass index (BMI) greater than 30 kg/m2 (Table 9.1). The group with the worst form of the disease, Class III obesity, is the most difficult to treat. The options for treatment in this group include pharmacotherapy, behavior modification, and surgery. Surgery has been shown to have the greatest impact and success in this group compared to any other form of treatment .