- Participants assigned to groups 1 or 2 will receive a diet intervention or diet and exercise intervention. They will be seen by the doctor for physical examination every 12 weeks for the first two years during the intervention, and then on an every 6 month basis. Routine laboratory testing will be done at the time of the visits as well. Other blood tests will be done to measure the effect of the diet and exercise interventions at the beginning of the treatment, at 6 months, and at 1 year from the start of the treatment. Additionally, one blood test will be done at the beginning of the treatment to look for hereditary differences in genes related to metabolism.