Study Design All subjects will undergo an initial GCRC visit, which will be outpatient or inpatient based on their subset assignment. At this first visit, medical evaluation, psychometric questionnaire administration and laboratory evaluation will occur as detailed below. Because fasting is required for the lab draws, the outpatient subjects will then be given a snack or meal by the GCRC dietician. Subjects will then meet with the GCRC dietician for a one-hour counseling session on weight loss.