Lifestyle Intervention for Treatment of Diabetes

Inclusion Criteria: * Men and women 21 years of age and older residing in the Forsyth County, North Carolina region. * Disease: Type 2 diabetes mellitus. * Overweight or obese: defined as body mass index (BMI) greater than 25 kg/m2 (\>27 if on insulin). * If not on diabetes medication, persons with hemoglobin A1c greater than or equal to 6.5% and less than 11.0% * If on diabetes medication, hemoglobin A1c greater than or equal to 5.0% and less than 11.0% * Blood pressure: BP ≤ 160/100 mmHg. * A usual source of medical care: The intervention may induce hypoglycemia and have other risks, and weight loss and increased physical activity may modify the need for drugs used to treat diabetes, high blood pressure, and lipids. Patients must have a source for ongoing care. Usual source of care will be documented via a "medical clearance" form with physician signature verifying that MD is aware their patient is participating in this trial. * Able to exercise: Increasing moderate intensity physical activity is an integral part of this intervention. Must be able to walk 1/4 mile without assistance. * Able to communicate in English * Other: Willing to give consent to participate in this research program, including random allocation to either study arm. Exclusion Criteria: * Poorly controlled diabetes: defined by hemoglobin A1c\>11% * Cardiovascular disease: Clinical history of cardiovascular disease, or newly diagnosed at screening. This includes myocardial infarction, heart failure, ischemic heart disease, stroke and other vascular disease. Persons suspected of having angina (chest pain) or other potentially ischemic symptoms will be required to be evaluated by their health care provider. * Weight Loss: Currently involved in a supervised medical or surgical weight loss program or with a history of prior weight loss surgery. * Age: We will exclude children (\<21 years) * Pregnancy: Diabetes during pregnancy has specific management criteria, and the role of weight loss via caloric restriction and increased physical activity is of uncertain efficacy and safety. Among women of child-bearing potential, planning to become pregnant within 12 months will be an exclusion criteria. Women who have recently given birth and are breast feeding are also excluded * Serious Illness with anticipated decreased life expectancy during the 2 year (24 month) time frame of the intervention, such as cancer diagnosis or treatment within the past 5 years (with the exception of non-melanoma skin cancer). * Inability to exercise: Patients who are wheel chair bound, have had an amputation, are undergoing treatment for lower extremity infections, or who self report being unable to ambulate 400 meters (1/4 mile) without assistance. * Participation in another clinical trial involving intervention(s) which affect any component of cardiovascular risk. Potential participants who are enrolled in purely observational studies remain eligible. * Renal disease: Persons with stage 3 chronic renal disease (estimated glomerular filtration rate \<60ml/min by the chronic kidney disease formula used by Wake Forest Baptist) will be excluded. * Other: Conditions/criteria likely to interfere with participation and acceptance of randomized assignment, including the following: inability/unwillingness to give informed consent, major psychiatric or cognitive problems (schizophrenia, dementia), self-reported active illegal substance or alcohol abuse, and clinical judgment.