Because cancer is a consuming disease, coupled with the great injury during surgery, radiotherapy and chemotherapy often cause patients to lose appetite, nausea, vomiting, diarrhea and other gastrointestinal reactions, which seriously affects patients’ nutrient absorption, causing extreme weakness, decreased resistance and even cachexia. At this time, dietary adjustment plays an extremely important role in patient’s recovery. At this time, patients should be given appropriate amount of basic nutrients in time to meet their nutritional requirements as much as possible in order to facilitate the recovery of the body. Tumor patients can carry out dietary therapy according to their physical constitution and the type of evidence they belong to, that is, to administer food according to evidence. According to Chinese medicine, each stage of the disease is different, and a disease can be manifested as different evidence according to the changes of etiology, physique, age, climate, geographical area or development stage, etc. The so-called evidence-based diet is to match food according to different evidence. If you have weakness, shortness of breath and sweating after chemotherapy or surgery, you should add qi benefit products to your diet, such as raw astragalus, American ginseng and Radix et cetera in soup, or ginseng or ginseng tablets in water; if you have weakness in the waist and knees, dizziness, insomnia, bloodlessness or low blood count, you should add angelica, rehmannia and jujube in soup, or jujube in water. In addition, lingzhi and wolfberry are very good tonic products, can be used in patients with qi deficiency and blood deficiency. If the patient shows symptoms such as abdominal distension, constipation, coughing with phlegm, etc., it is appropriate to use products to dispel evil, adding white buckwheat, winter melon, etc. to the diet, and avoiding products to supplement qi and blood; if the patient shows symptoms such as general coldness, cold pain in the stomach and epigastrium, warmth and pressure, etc., it is appropriate to use products to warm the interior and disperse, adding ginger, clove, pepper, cinnamon, pepper, wicker, etc. to the diet; if internal heat is seen, such as dry mouth, bitter mouth, etc., it is appropriate to use products to clear the drainage If the evidence of heat toxicity is strong, manifested as mouth sores, redness and swelling of wounds, yellow urine, thirst and irritability, fever that does not subside, dry stools, etc., it is advisable to eat more fruits, watermelon, rice porridge, and some cool and stomach-healthy, thirst-quenching food, do not eat too much warm, dry, greasy things, it is advisable to use certain vegetables with the effect of heat detoxification, such as mustard, lettuce, amaranth, dandelion, fishy grass, etc. In addition, if the patient has abdominal distension, loose stools and no appetite soon after surgery, it is advisable to use yam, lotus seeds, hawthorn, malt, Chen Pi, etc. to strengthen the spleen and stomach, and use medicinal porridge, such as yam porridge, barley porridge, etc. as a tonic, and it is not advisable to use harsh tonic products regardless of the stomach and appetite because the postoperative qi and blood are greatly injured. Even the same disease can show many different types of evidence, and there are also differences in the selection of food. For example, if intestinal cancer has diarrhea, unpleasant stool and white mucus in stool, it is mostly due to dampness and heat, so it is appropriate to use Amaranthus and dandelion to clear heat and dampness; if it is due to food stagnation and undigested food in stool, it is appropriate to use radish and hawthorn; if it is due to weakness of spleen and stomach, which is manifested as not thinking about eating and drinking and loose stool, it is appropriate to use yam and lotus seed; and if it is manifested as belching, burping and abdominal distension, it is due to gas stagnation. If the symptoms are dry mouth, red tongue and no coating, it is stomach yin deficiency, so it is appropriate to use sage, maitake and fresh fruits. In a word, the identification of food can regulate the function of the internal organs of the body, re-establish the balance of the internal environment, maintain the nutrition required by the patient, and really achieve what is lacking, and can be digested and absorbed, do not disregard cold, heat, warm, cold, a brutal tonic. In addition, when administering food, we should pay attention to balanced diet, i.e. to enrich the variety of food as much as possible, to change the production method constantly, to meet the patient’s “color”, “fragrance” and “taste” of food. We should pay attention to a balanced diet, i.e., we should try to have as much variety of food as possible, constantly change the preparation methods, and meet the patient’s requirements for “color”, “flavor” and “taste” of food and various forms of soup, soup and congee. To avoid anorexia and partiality of food, to meet the needs of nutrition and “sex” and “taste” required by patients for recovery, and to promote recovery. In addition, some tumor patients should avoid eating sweet food and greasy food, such as sweet potato, corn, doughnut, oil cake, etc. due to clinical manifestations of tumor or adverse reactions in treatment, such as loss of appetite, nausea and vomiting, gastric distension, etc. Instead, light food, such as soup made of fresh vegetables, mushrooms, nori and fruit juice such as lotus root, water chestnut, apple, etc. should be avoided. If you see edema in the limbs, it is also advisable to eat less salt and pickled products, and you should not eat cold, cold, fatty and sticky products to prevent re-injuring the spleen and stomach and increasing the retention of water and dampness. Diet should also be adapted to the four seasons of the climate, the four seasons alternate climate, humans must follow the laws of nature and not contradict. In the spring and summer, the Yang energy is strong and everything is vibrant, so we should try not to eat meat and other warm and tonic products; in autumn, when everything is dry and depressed, patients often have dry mouth and tongue, and even epistaxis and cracked lips, so we should try to eat less hot and spicy food and eat more fruits with more water; in winter, when it is cold, we should eat less cold and hurtful food, and we should eat warm and tonic products.