Obese sugar disease can be recovered after weight loss, but the reversal rate is 70-80%. According to the latest New England Journal, for refractory type 2 diabetes mellitus combined with obesity, the effect of surgical treatment is better than that of traditional drug treatment, but it also depends on the timing of surgery. If the pancreatic function is already weak, even after the surgery will benefit very little, so obese patients with type 2 diabetes need early surgical intervention. Obese patients with type 2 diabetes mellitus can be cured after surgery, because after weight loss surgery, food intake and absorption are reduced, weight is reduced, and all kinds of pancreatic islet functions can be greatly improved, and insulin secretion will return to normal. In addition, bariatric surgery can lead to increased insulin sensitivity. Weight loss surgery includes sleeve gastrectomy and bypass surgery. Gastric bypass surgery is better than sleeve gastrectomy for obesity combined with type 2 diabetes mellitus, but the risk of surgery and the chance of complications are greater than sleeve gastrectomy.