Diabetes Dietary Study- Low Carbohydrate and Low-Fat Diets in Type 2 Diabetes

Obesity is not only a risk factor for type 2 diabetes but it also frequently increases the need for insulin requirement in people with type 2 diabetes who are overweight or obese. However, since insulin is a lipogenic hormone, insulin or sulfonylurea therapy that increases circulating insulin levels often results in additional weight gain. Controlled-carbohydrate "ketogenic" diets have been popular as an alternative way of losing weight, but little is known about the safety and efficacy of using a ketogenic approach in the management of overweight/obese patients with type 2 diabetes. The proposed study will randomize a group of 126 overweight or obese (BMI \> 25 and \< 40) adults with type 2 diabetes to either a low-carbohydrate or a low-fat weight loss diet. The primary study endpoint will be six and twelve month changes in glycemic control as measured by hemoglobin A1c (HbA1c). Secondary endpoints include adiposity (BMI, body composition and fat distribution); blood glucose patterns (from self-monitoring records); change in antidiabetic medications (potential decrease in number and dosage), lipids, insulin sensitivity from a meal tolerance test, other metabolic markers (C-reactive protein, leptin) and participants' lifestyle (physical activity and diet) and perceptions of satiety, quality of life, mood, and well-being.