They looked at over 4,000 diabetics who had gastric bypass surgery for weight loss, following their cases over many subsequent years. Almost seven in 10 had a “complete diabetes remission” within five years of surgery. (Remission was defined as non-diabetic lab values on blood tests and absence of diabetic drug use.) Of those going into remission, 35% redeveloped diabetes within five years of surgery. Those with the more severe or longstanding cases of diabetes before surgery were more likely to have a recurrence of diabetes.
So it looks to me like, on average, gastric bypass surgery “cures” half of the cases of type 2 diabetes, as measured five years after surgery. As the years pass, even more failures will arise. Nevertheless, that’s an impressive improvement. Given the potential complications of bypass surgery, I’d try a very-low-carb diet before going under the knife. Examples are Dr. Bernstein’s Diabetes Solution and Conquer Diabetes and Prediabetes.
PS: Cure or remission of type 2 diabetes could be defined in other ways. For instance, a more reliable definition of cure might include return of normal pancreas/insulin function as judged by insulin levels and insulin sensitivity. If you have normal blood sugar levels and hemoglobin A1c, yet have ongoing insulin resistance, you’re more likely to develop overt diabetes going forward.