Obesity Risk in African American Women is Determined by a Diet-by-phenotype Interaction

Obesity Risk in African American Women is Determined by a Diet-by-phenotype Interaction

The Scientific Premise of this study is that the high level of obesity displayed by African American (AA) women is due to the ability to secrete large amounts of insulin when sugary foods are consumed. When AA women eat a diet rich in starchy or sugary food (a "high-glycemic" diet that stimulates insulin secretion), the food that is eaten is stored as fat rather than being burned as fuel. The investigators previous research has suggested that AA women have an easier time losing weight and keeping it off when eating a low-glycemic diet. The proposed study will be the first randomized clinical trial to test the effect of high and low glycemic diets for weight loss and weight-loss-maintenance in obese AA women.

Inclusion Criteria:

• BMI 30-45 kg/m2
• Sedentary to moderately active (<2 hours/wk of moderate, structured, intentional exercise.
• Normal menstrual cycle

Exclusion Criteria:

• History of eating disorder
• daily use of tobacco (>1 pack/wk)
• change in weight greater than 5 pounds in previous 3 months
• presence of any condition (e.g. PCOS) or use of any medication (e.g. glucocorticoid) deemed by the project physician to interfere with study outcomes
• applicants will be screened with a standard oral glucose tolerance test. If a participant's 2 hour glucose if >200, they will not be able to enroll in the study.