High Carbohydrate vs. High Fat Diets in the Treatment of Obesity (JBR 0512)

Participation in this study requires 2 screening visits to the outpatient clinic, and if participants qualify, 10 inpatient study weeks.

Subjects will be admitted to the Rockefeller University Hospital for the 10 week in-patient phase of the study. The first 2 weeks consist of a weight stabilization period, during which subjects will be required to consume an average American diet. This is followed by the 6 week weight loss period where subjects will be randomized to either a low calorie high carbohydrate or a low calorie high fat/protein diet. On both diets there will be a 50% calorie deficit compared to the weight stabilization period. This will be followed by a 2 week weight maintenance period during which calories will be added to the diet to maintain the new weight. Appropriate adjustments will be made to keep the subject's weight stable.

During the entire inpatient study, subjects will consume one multivitamin per day (Centrum, always complete, from A to Zinc) and one iron supplement per day. In addition, unlimited access to zero calorie liquids (water/diet soda) will be available and will be encouraged to maintain one's usual activity level.

Females of reproductive age, need to make sure that they do not become pregnant during the inpatient study. Urine will be tested for pregnancy once during the stabilization and weight maintenance phases of the study.