7. Obesity Management for the Treatment of Type 2 Diabetes

There is strong and consistent evidence that obesity management can delay the progression from prediabetes to type 2 diabetes (1,2) and may be beneficial in the treatment of type 2 diabetes (3–8). In overweight and obese patients with type 2 diabetes, modest and sustained weight loss has been shown to improve glycemic control and to reduce the need for glucose-lowering medications (3–5). Small studies have demonstrated that in obese patients with type 2 diabetes more extreme dietary energy restriction with very low-calorie diets can reduce A1C to ,6.5% (48 mmol/mol) and fasting glucose to,126mg/dL (7.0mmol/L) in the absence of pharmacological therapy or ongoing procedures (7,9,10). Weight loss–induced improvements in glycemia are most likely to occur early in the natural history of type 2 diabetes when obesityassociated insulin resistance has caused reversible b-cell dysfunction but insulin secretory capacity remains relatively preserved (5,8,10). The goal of this section is to provide evidence-based recommendations for dietary, pharmacological, and surgical interventions for obesity management as treatments for hyperglycemia in type 2 diabetes.