Surgery is a big deal for patients, so many of them are concerned about post-operative results during the clinic. To answer this question, let’s talk about the principle of surgery: Sleeve Gastrectomy This surgery limits the caloric intake of solid food. It also regulates hormones and reduces the secretion of hunger hormone (Ghrelin), so that patients do not feel hungry easily after surgery. There is no effect on the patient’s absorption, and the patient can make up for it when he or she is weak. However, excessive calorie intake can also occur if high-calorie foods are eaten or (and) high-calorie liquids are consumed. Gastric bypass surgery This surgery, which reconstructs the patient’s digestive tract, is so effective in lowering blood sugar that obese type 2 diabetic patients with ≥ 1/2 normal pancreatic beta cell secretion can control their blood sugar without relying on drugs through the surgery. This surgery will affect absorption and patients will need to take micronutrients for life. Although it affects the patient’s absorption, obese friends are born with good absorption ability. It is still possible to rebound if you don’t pay attention to controlling calorie intake. Research shows that patients can generally lose 70-80% of their extra weight. After surgery, patients will not return to their original weight, however, if high-calorie food and high-calorie drinks are not controlled, the weight loss effect will not be obvious. Patients with the same BMI have lost 60 pounds in 3 months after surgery, while some have lost 30 pounds after surgery, which is the result of not controlling calorie intake. This is why when discharged from the hospital, patients are instructed not to drink carbonated gas drinks and not to crave high-calorie foods such as melons and nuts. Surgery is not the end of obesity, but a way for patients to get back to a state of healthy eating habits. Surgery allows high weight patients to put on the emergency brake and have a chance to make new dietary choices. It is crucial for patients to continue with their old eating habits or to change into good eating habits.