Weight loss as a cure for Type 2 diabetes: fact or fantasy?

Although individuals with obesity and Type 2 diabetes are insulin resistant, pancreatic b-cell failure is the core defect that distinguishes individuals who eventually develop diabetes. This process is known to occur well before the onset of hyperglycemia. Although clinical trial data support the effectiveness of intensive lifestyle modification in delaying the onset of diabetes in obese subjects, less is known about the effects of, and mechanisms underlying, bariatric surgery, particularly gastric bypass surgery, on diabetes. The paper under evaluation clarifies the role of both lifestyle intervention and gastric bypass surgery on pancreatic b-cell function and raises questions regarding the role of weight loss versus incretin-related mechanisms on recovery of b-cell failure. INSET: Key issues. [ABSTRACT FROM AUTHOR]