Obesity and related metabolic diseases have become a chronic disease that is a threat to human health. Bariatric surgery can effectively and long-term reduce excess body weight and relieve related metabolic diseases, including type 2 diabetes. Laparoscopic gastric bypass surgery and laparoscopic sleeve gastrectomy are commonly used in bariatric surgery. Laparoscopic sleeve gastrectomy due to simple operation, good weight loss, and metabolic disease control effect, which is more widely used. However, there are several studies that show an increased chance of gastroesophageal reflux disease after laparoscopic sleeve gastrectomy. Long-term gastroesophageal reflux may lead to Barrett's esophagus or esophageal cancer. Nowadays, the cause of gastroesophageal reflux disease after sleeve gastrectomy is not clear and precautionary measures are not precise.

In this study, prospective randomized controlled trials were conducted to explore the possible causes of liver funnction after bariatric surgery and to explore ways to prevent liver functione after bariatric surgery

With the social development and changes in the lifestyle, the incidence of obesity and type 2diabetes is rapidly increasing. In 2010, the global incidence of type 2 diabetes was 8.3% in adults, 11.6% in China and 50.1% in China. In overweight and obese people, the prevalence of type 2 diabetes also increased significantly, and the prevalence of type 2diabetes in those people with BMI> 30 reached 18.5-23%. Diabetes-induced cardiovascular and cerebrovascular diseases, renal insufficiency and other complications, seriously affecting the quality of life of the patients, endangering the safety of life, the treatment of type 2 diabetes and related complications to public health expenditure has brought tremendous pressure.

Traditional medical methods are difficult to achieve long-term and effective control of type 2 diabetes. Surgery has been shown to achieve 75-95% long-term relief of obesity in patients. Roux-en-Y gastric bypass (Roux-en-Y gastric bypass, RYGB) and laparoscopic sleeve gastrectomy are most commonly used. Among them, laparoscopic sleeve gastrectomy is relatively simple, low incidence of complications, lower operating costs, and gradually become the most important surgical methods of weight loss and metabolic disease surgery. Numerous clinical studies are shown that sleeve gastrectomy in patients with type 2 diabetes has the same therapeutic effect as gastric bypass with a complete remission rate of 70-90% for T2DM.

For the choice of surgical approach, numerous studies have shown that BMI ≧ 45, the general choice of gastric bypass surgery, BMI <45, participants can choose sleeve gastrectomy. The remission rate for T2DM, sleeve gastrectomy has a good result for young patients with shorter duration. In China, the BMI less than 45 is majorities.

According to the previous survey in 2012, the newly diagnosed diabetes patients in China constituted more than half of all diabetic patients. Since bariatric surgery is relatively simple, so bariatric surgery is easier to popularize in China and has wide application prospect.

Inclusion Criteria:

• For the choice of surgical approach, numerous studies have shown that BMI ≧ 45, the general choice of gastric bypass surgery, BMI <45, you can choose sleeve gastrectomy. The remission rate for T2DM, sleeve gastrectomy has a good result for young patients with shorter duration. In the investigator's country, the BMI less than 45 is majorities.

Exclusion Criteria:

• BMI<27.5