The origin of weight loss surgery, the evolution of the procedure and the change of concept Nowadays, weight loss has become a lifelong pursuit for many people. However, after trying various weight loss programs such as exercise, diet, medication, acupuncture, etc., the weight always returns to the original point or even bounces back, and the results are not obvious. In recent years, more and more obese patients have undergone successful surgical weight loss cases to verify the effectiveness and safety of weight loss surgery: the famous American girl band lead singer, Kani? Wilson, because of obesity chose to undergo weight loss surgery, after the operation, her weight quickly lost about 150 pounds, instantly transformed into a slender lady, and thus also on the best-selling “People” magazine in the United States. American Idol judge Randy? Jackson underwent weight loss surgery in 2003, successfully losing 110 pounds and relieving type 2 diabetes, after he weighed 355 pounds. The most famous is the Argentine soccer star Maradona. After retiring, Maradona kept gaining weight: he underwent weight loss surgery in 2005 and has since regained his normal physique and started his coaching career …… Seeing this, you must want to know more. So, let’s learn about the past life and present life of weight loss surgery. Origin and evolution of bariatric surgery In 1925 Leyton reported on gastrojejunostomy for the treatment of patients with duodenal ulcer (combined with diabetes) and found that diabetes improved after surgery, this report of clinical observation is considered to be the earliest observation of the therapeutic effect of metabolic bariatric surgery on diabetes. The original idea came from the short bowel syndrome, which induces dyspepsia by shortening the length of the small intestine, thereby reducing absorption, so jejunocolonic bypass surgery was considered at the time to be the best way to reduce weight. However, almost all patients developed diarrhea and electrolyte disturbances, and even liver failure after the surgery. By the 1970s, jejuno-ileal bypass gradually replaced jejuno-colonic bypass as the first widely used bariatric procedure. 65% of patients can lose more than 50% of their excess weight through the procedure. However, the rate of postoperative complications remained high, and this surgical procedure was phased out. In 1966, Mason and Ito, the fathers of weight loss, observed in their clinical practice that patients with peptic ulcer disease could maintain a low weight status after a major gastrectomy, so they performed the “primitive gastric bypass”, i.e., reconstructing a gastric bursa with 10% of the gastric volume preserved in the fundus and performing a BII-type anastomosis (a major distal gastric resection followed by joining the stomach to the small intestine). The results of this procedure were satisfactory for weight reduction. In 1976, Griffen et al. modified this procedure into a gastric bypass-gastrojejunostomy (direct anastomosis of the stomach and small intestine without cutting the stomach), which effectively reduced the symptoms of bile reflux and esophagitis that existed in the original gastric bypass. Later, the importance of gastric restriction in gastric bypass was discovered, so various improved gastric restriction procedures emerged on this basis. Among them, vertical banded gastroplasty (VBG) emerged in the mid to late 1980s and became the mainstream at that time. However, the long-term weight loss effect of VBG was not satisfactory, so gastric bypass gradually became the mainstream procedure in bariatric surgery in the 1990s. In response to the phenomenon that gastric bypass restricts intake mainly and separates biliopancreatic fluid from gastric fluid, people thought of malabsorption combined with gastric restrictive surgery. So some doctors designed biliopancreatic bypass surgery and duodenal transposition, but although these two surgeries were ideal for weight loss, they were complicated to operate and had relatively more complications, and were usually applied to super obese patients (BMI〉50), thus they were not widely carried out. After Wilkinson pioneered gastric banding in the 1980s, adjustable gastric banding was considered almost as effective as gastric bypass for weight loss in Europe and Australia. However, as the years of use and the number of cases increased, it became apparent that the complications of gastric banding were far greater than had been thought, and long-term observations showed a high rate of patient weight loss failure and reoperation. With the popularity of laparoscopic techniques, Wittgrove et al. first reported laparoscopic gastric bypass in 1994, and gastric bypass entered the minimally invasive era and gradually became the most popular weight loss procedure worldwide. Since the 1990s, sleeve gastrectomy has gradually gained importance, which is mainly inspired by the removal of the fundus and large part of the gastric body in patients with ulcers, and is used for weight loss initially mainly in super obese patients (those with BMI > 60 kg/m2) or in patients with great surgical risk. Sleeve gastrectomy was performed before gastric bypass or biliopancreatic bypass to allow appropriate weight loss before further bariatric procedures. However, it has been found that about 70% of super obese patients do not require a second step after sleeve gastrectomy. As a result, sleeve gastrectomy has gradually been accepted as a stand-alone procedure for weight loss and is now a routine procedure for weight loss. The 3rd World Conference on the Treatment of Type 2 Diabetes and the 2nd Diabetes Surgery Summit, held in London, United Kingdom, in September 2015, issued a joint global statement on the surgical treatment of diabetes, with bariatric surgery as the latest clinical guideline for the surgical treatment of type 2 diabetes, which recommended four procedures: gastric sleeve resection, gastric bypass, adjustable gastric banding, and biliopancreatic bypass-duodenal These four procedures currently account for 49%, 43%, 6% and 2% of metabolic bariatric surgery worldwide, respectively, with the two mainstream procedures, gastric sleeve resection and gastric bypass, accounting for 92% of the total. It is believed that with the in-depth research on the principles of weight loss and glucose reduction, more new procedures will emerge, and bariatric surgeons will continue to work hard in the exploration of the procedures. Changes in the concept of bariatric surgery For bariatric surgery, the whole society, including internists and dietitians, has a gradual process of understanding. Before there was bariatric surgery, the mainstream methods of weight control in the medical field were diet and exercise. Bariatric surgery originated in the 1950s and has undergone a long and difficult development process, from being rejected to gradually being recognized and then widely accepted, eventually becoming an important subspecialty of general surgery, the whole process has spanned more than half a century, and has now become the ‘gold standard’ for the treatment of morbid obesity. The philosophy of bariatric metabolic surgery has been constantly updated during the course of its development. After the end of World War II in 1945, the obesity population increased dramatically and bariatric surgery emerged, the main purpose of which was to treat obesity, hence the name of the discipline at the time, “bariatric surgery”. In the 1980s, researchers discovered that bariatric surgery could alleviate not only type 2 diabetes but also a variety of coexisting metabolic syndromes, hence the concept of metabolic surgery. Currently, the most common name used worldwide is “bariatric metabolic surgery”. Although weight loss surgery has been recognized as effective in weight control for 60 to 70 years in the United States, it has been widely recognized and accepted in the last 30 years, and in China for 20 years. For the surgery itself, it has matured in the last decade and has entered the era of minimally invasive surgery, and there is more understanding of its basic principles, which is a big progress. Clinical practice has benefited the majority of obese patients while also allowing endocrinologists and dieticians to see the effectiveness and safety of the procedure, which was eventually fully recognized by the medical community in China and written into the treatment guidelines for obesity and diabetes. Bariatric surgery is increasingly becoming a mature procedure, with hundreds of thousands of cases performed worldwide in 2014 alone. The surgical treatment of obesity and diabetes in China began in 2000; in 2012, the Obesity and Diabetes Surgeons Committee of the Chinese Physicians Association, Branch of Surgeons, was established to provide standardized training for surgeons and to carry out a lot of popularization activities for patients. More and more fat people “regain the joy of life”.