Medical nutrition therapy plays a major role in diabetes management. Macronutrient composition has been debated for a long time. However, there is increasing evidence that a modest increase in dietary protein intake above the current recommendation is a valid option toward better diabetes control, weight reduction, and improvement in blood pressure, lipid profile, and markers of inflammation. Increasing the absolute protein intake to 1.5-2 g/kg (or 20-30% of total caloric intake) during weight reduction has been suggested for overweight and obese patients with type 2 diabetes and normal kidney function. Increased protein intake does not increase plasma glucose, but increases the insulin response and results in a significant reduction in hemoglobin A(1c). In addition, a higher dietary protein intake reduces hunger, improves satiety, increases thermogenesis, and limits lean muscle mass loss during weight reduction using a reduced calorie diet and increased physical activity. It is preferable to calculate protein intake for patients with diabetes as grams per kilogram of body weight and not as a fixed percentage of total energy intake to avoid protein malnutrition when a hypocaloric diet is used. The relationship between protein intake as grams per kilogram of body weight and albumin excretion rate is very weak, except in hypertensive patients and particularly in those with uncontrolled diabetes. A protein intake of 0.8-1 g/kg should be recommended only for patients with diabetes and chronic kidney disease. Other patients with diabetes should not reduce protein intake to less than 1 g/kg of body weight. This review discusses the effects of different amounts of protein intake in a diabetes meal plan. It particular, it discusses the effects of protein intake on renal function, the effects of protein content on diabetes control, and the effects of increased dietary protein on body weight.