The stomach plays an important role in the human body such as food intake and digestion, and either subtotal or total gastrectomy seriously affects patients’ gastric function. Therefore, postoperative patients with gastric cancer should pay special attention to their diet to prevent various postoperative complications. Commonly used guidelines are as follows: 1. Dietary care guidance during postoperative hospitalization: For patients after subtotal gastrectomy, they can drink a small amount of water on the day after stopping gastrointestinal decompression, half amount of liquid food on the second day and full amount of liquid food on the third day, with slow intake, 6-8 times a day. Foods high in protein, vitamins and a variety of minerals are preferred, while foods prone to flatulence, such as dairy products, beans, corn, potatoes, carbonated beverages, etc., should be avoided. If the recovery after surgery is normal, semi-liquid food can be introduced on the fourth day, and universal food can be introduced after 10~14 days. For patients after total gastrectomy, they can start to eat sugar water or rice soup on the second day after stopping gastrointestinal decompression, and gradually increase the amount, and start to eat semi-liquid food from the fifth day, and if the patients have no special discomfort, they can enter full liquid food on the sixth day, and change to semi-liquid food from the tenth day. In short, if the patient develops abdominal distension and pain while eating during hospitalization, he should stop eating and notify the doctor to determine whether there is intestinal obstruction or anastomotic fistula and other possibilities. The general principle of diet for postoperative patients with gastric cancer is to have a small number of meals and gradual progress. The diet should be light and rich in high vitamin and protein, and easy to digest. Patients can eat eggs, dairy products, lean meat, tofu, soy milk, fresh vegetables and ripe fruits. Meanwhile, patients should chew and swallow slowly when eating, and use their tongues to stir more often with saliva, so that the oral cavity can replace part of the digestive function in the stomach, which is quite important in the early postoperative dietary recovery of gastric cancer. In addition, patients should avoid eating stimulating foods such as too cold, too hot, raw and hard, fried, strong tea and wine after surgery. In addition, the absorption of iron is affected by the reduction of gastric acid after surgery, so some iron supplements can avoid iron deficiency anemia. For patients after total gastrectomy, it is better to take intravenous supplementation of folic acid, vitamin B12 and other trace elements once a year. Some patients with gastric cancer may experience dizziness, pallor, vertigo, palpitations, sweating, nausea, vomiting, or abdominal pain, bloating, diarrhea, etc. half an hour after eating in the early postoperative period. This condition may be what is clinically known as dumping syndrome. Its pathogenesis is that food can enter the small intestine quickly due to the surgical removal of the pyloric sphincter. If the food contains high sugar content or high osmotic pressure, a large amount of extracellular fluid can be drawn into the intestinal lumen for a short period of time after entering the small intestine, causing a decrease in blood volume. At the same time, because the food enters the small intestine quickly, the intestinal cavity is forced to swell suddenly, and intestinal peristalsis increases, stimulating the abdominal nerve plexus. Under the superimposed effect of the above factors, the patient will experience dizziness, pallor, vertigo, palpitations, sweating, nausea, vomiting, or abdominal pain, bloating, diarrhea, etc. half an hour after eating. At this time, the patient should be immediately put in bed to relieve symptoms, and intravenous isotonic solution can be supplemented to maintain blood volume if possible. For dumping syndrome, the current treatment method is mostly preventive. That is, the patient is instructed to eat small amounts and drink as little water as possible when eating. This is because liquids can quickly dissolve food and form a hypertonic solution to the small intestine, triggering or aggravating dumping syndrome. In addition, patients can lie flat for 20-30 minutes after eating depending on their specific situation can control or reduce symptoms.