Laparoscopic gastrectomy is also called sleeve gastrectomy. Because surgery will cut off 80% of the stomach volume, in addition to reducing food intake, it will also reduce the secretion of ghrelin, a hormone that stimulates appetite, so appetite will also decline. About 10- 15 body mass index or 70% excess weight can be lost within two years after operation. For people with high body mass index (over 40 years old) who are difficult to reduce their food intake, stomach reduction surgery can achieve ideal weight loss effect.