The dietary approach three days before a colonoscopy should be based on fluid, easily digestible foods. Fluid, easily digestible foods, such as rice pudding and chicken broth, can avoid food residue left in the intestines and facilitate good preparation for bowel cleansing. If the examination is performed in the morning, patients should pay attention to the diet of the night before, it is best to eat only some soup food, so as not to cause food accumulation in the intestines. On the day of the test it is important to have an empty stomach and not eat anything, including water. If the examination takes place in the afternoon, in the morning the patient can drink some sugar water appropriately to avoid the symptoms of hypoglycemia. Other than this food, it is best not to eat anything else to ensure that the examination goes smoothly. On the day of the examination, it will be decided according to the actual situation of the patient whether to drink sugar water or not, and any other food except this should be fasted until after the examination to see if it can be eaten according to the results of the examination.