When it comes to weight loss surgery inside the gastrectomy, many fat people want to know whether this surgery has any effect on the body or not? The first thing we need to understand is what is gastrectomy surgery and how it is actually done? Many people can guess from the literal meaning of the approximate, but what is a specific surgery, we are still confused. In April 2008, this gastric surgery was included in the regular weight loss surgery by the U.S. Food and Drug Administration, and now more than 200,000 people around the world have done the surgery. Our stomach, in fact, is very much like a large wine bag-shaped bag, small on the left and large on the right, with the esophagus attached to the top and the small intestine attached to the bottom. The large part of the stomach is removed along the long axis of the stomach, leaving a “banana-shaped” stomach with a volume of about 60-80 cm, while preserving 2-6 cm of the sinus above the pylorus in the direction of the large curve of the stomach. The stomach wall area is reduced, the area where we digest food is reduced, and the entire volume of the stomach is only 1/3. Every time we eat a little bit of food, we get full, and we lose weight naturally because we consume less calories every day. The entire surgery is done minimally invasively with a laparoscope, which requires several holes to be made in the stomach and a camera lens and scalpel to be placed inside. The doctor will remove 2/3 of the patient’s stomach under the belly through the computer monitor. The stomach becomes smaller, and eating too much will make you nauseous and vomit. Everyone has the impression that fat people’s stomachs are bigger because of overeating and eating, now although the stomach is cut off 2/3, but if you do not control your diet in the future, the stomach will still get bigger? There are two main reasons why the stomach becomes larger: the number of cells in the stomach wall increases and the volume of the cells in the stomach wall becomes larger. When our organ development is complete, the total number of cells in the stomach lining is fixed for the entire stomach and will not increase in the future. Now, if 2/3 of the stomach is cut off, it means that 1/3 of the stomach wall cells are left. At the same time, there is a limit to the size of each stomach lining cell. Therefore, the stomach may increase in size after the surgery, but the expansion is limited. Moreover, people who have undergone gastric resection surgery will immediately suffer from nausea and vomiting once they eat a little too much. After more than 10 years of development of bariatric surgery in China, the number of cases receiving bariatric surgery for obesity and type 2 diabetes is now increasing year by year, showing a good development trend. However, bariatric surgery is not a mere surgery, it is a systematic treatment that consists of three parts: professional preoperative assessment, high-quality surgery, and medium and long-term postoperative health management to ensure the efficacy of the surgery.