15. High risk for silent heart diseases as evidenced by high levels of high-sensitivity C-reactive protein or homocysteine in blood, or being overweight or obese. In addition patients with high cholesterol or a family history of heart disease will be evaluated by a cardiologist to determine their eligibility for participation. The cardiologist might request additional tests if he deems it necessary to ensure fitness for participation (ie treadmill stress test). Specifically the cardiologist involved will review the findings of 1) an inability to reach these endpoints, 2) the development of chest pain, 3) significant ST segment changes, 4) significant arrhythmias, and 5) an inability to appropriately increase blood pressure or heart rate with exercise in order to determine if the participant is suitable for inclusion in the study.