The reasons for not being able to eat with anesthesia are the reasons for the surgery itself and the reasons for anesthesia, as follows: 1. Surgical reasons: If the stomach or gastrointestinal area is operated on, eating will affect the surgical operation afterwards; 2. Anesthesia reasons: After anesthesia, patients will lose consciousness and perception and cannot master some of their physiological reflexes by themselves, which may cause reflux or vomiting, leading to respiratory inhibition and asphyxia. In general, patients are advised to abstain from water 2 hours before surgery and from food 4 hours before surgery to avoid reflux of food into the trachea, leading to asphyxia.