Type 2 diabetes is a global problem, accounting for 85% to 90% of the total number of diabetic patients, and the number of people with type 2 diabetes in China has reached 50 million. Diabetes is often combined with hyperlipidemia and hypertension, which brings about serious complications such as cardiovascular disease, renal damage and limb necrosis (see below), which seriously affect the quality of life and life expectancy of patients, such as cerebrovascular disease caused by diabetes leading to stroke, which brings a heavy burden to patients and society. Although multifactorial interventions such as lifestyle improvement, glycemic control, antihypertensive, lipid-lowering and antiplatelet therapy have been used to minimize the occurrence of complications in diabetic patients, their prognosis is still unsatisfactory. type 2 diabetes is also progressive, and studies have confirmed that the function of pancreatic β-cells in diabetic patients declines rapidly at a rate of 20% per year. Combined application of hypoglycemic drugs, it is difficult to ensure that patients return to normal blood glucose and avoid the emergence of various serious complications caused by diabetes. Insulin has benefited many patients, but insulin resistance can develop at a later stage, making treatment difficult. In order to treat diabetes, attempts have been made to achieve the goal through islet or pancreas transplantation, but the clinical treatment is very unsatisfactory, with embarrassing results, and is only at the stage of animal experiments. Second, what is type 2 diabetes radical surgery What people call type 2 diabetes radical surgery is also called gastric diversion surgery (GBP). The unique feature of gastric diversion surgery is that it changes the normal physiological flow of food. The surgery is completed by blocking the stomach, cutting off the jejunum, gastrointestinal anastomosis, and enteroenteric anastomosis (duodenal and jejunal anastomosis). The principle of surgery is shown in the figure: The postoperative GI tract is divided into two areas: (1) food diversion area: it refers to the majority of the stomach, duodenum and part of the proximal jejunum, which is no longer stimulated by food after surgery, resulting in a decrease in the secretion and synthesis of “diabetogenic factors”. (2) Food flow zone: A small part of the stomach, distal jejunum and ileum, which receives undigested or incompletely digested food in advance, leading to an increase in the secretion of hormones, which increases insulin sensitivity through the “intestine-islet axis” and promotes insulin secretion. This increases the sensitivity of insulin through the “intestine-islet axis” and promotes insulin secretion, thus achieving the effect of blood sugar control. Which type 2 diabetic patients are suitable to receive gastric diversion surgery? (i.e. indications) Inclusion criteria for gastric diversion surgery: 1. Meet the diagnostic criteria for type 2 diabetes mellitus. 2. 2. Islet function is in the compensatory phase (plasma insulin level > normal value). 3, History of diabetes <15 years, age <65 years. 4.Voluntary acceptance of gastric diversion surgery and signed consent form. Among them, patients with obesity and metabolic disorder syndrome (e.g. cardiovascular disease, fatty liver, lipid metabolism disorder, sleep apnea syndrome, etc.) are particularly well treated. Which type 2 diabetic patients are not suitable for gastric diversion surgery? (i.e. contraindications) Exclusion criteria for gastric diversion surgery: Gastric diversion surgery is not suitable for those who have one of the following conditions 1. Advanced diabetes mellitus, islet failure with fasting serum insulin or 2 hours postprandial serum insulin below the normal range. 2.Patients with a history of diabetes mellitus > 15 years or age > 65 years old, suffering from serious organic diseases that cannot tolerate surgery, such as heart failure, kidney failure and other serious complications. 3, Gastrointestinal tract dysfunction, moderate to severe diabetic gastroparesis. 4. Patients with autoimmune diabetes mellitus who are positive for serum insulin antibody (ICA) or glutamic acid decarboxylase antibody (GADA) should be considered as appropriate. 5. Patients with systemic infections not effectively controlled and patients with cerebrovascular accidents.