Should tumor patients avoid eating during radiotherapy and chemotherapy? Will eating the so-called “hairy food” cause tumor progression? This is a question that we both doctors and patients have to face and answer frequently. Chinese folklore used to call foods such as goose, rooster, pork, carp, shrimp, dog, mutton, etc. as “hairy things”, some people say that tumor patients cannot eat hairy things, and in some places it is said that tumor patients cannot eat seafood and fish without scales, etc. Can tumor patients eat “hairy things” and should they avoid them? Can tumor patients eat “hairy food” and should they avoid eating it? From the medical point of view, “hairy food” refers to the food that is particularly likely to trigger the recurrence of certain diseases or aggravate the diseases already occurred. The folklore of these “hair” is mainly related to the occurrence and development of allergic diseases or skin sores and swellings, such as urticaria, eczema and other allergic skin diseases. Mostly due to the patient’s endowment intolerance, allergic to certain substances, so in the diet should be avoided fish, shrimp, crab and other diets containing foreign protein. Chinese medicine believes that Yang sores and swellings are mainly caused by dampness, heat and fire. From the perspective of modern pathology, tumor is neither an allergic disease nor a sore and canker sore in the traditional sense, and there is no evidence to prove that these “hair products” are necessarily related to the recurrence and metastasis of tumor. Some seafood, such as sea cucumber, seaweed, kombu, squid, etc., are also commonly used as food and medicine in anti-cancer treatment. It is true that “taboo” in Chinese medicine means that in order to avoid harm to the body and recovery of disease due to improper diet, patients should have taboos in diet, and “taboo” is not only for tumor patients, but all diseases. However, the “taboo” mentioned by Chinese medicine does not mean that tumor patients cannot eat chicken, fish, shrimp, seafood and other foods as the folklore says, but emphasizes the selection of food according to the evidence and the taboo of food according to the evidence, that is, to pay attention to the taboo of diet according to the specific conditions of patients. For example, snapper can be eaten by patients with internal heat of yin deficiency, while it is not suitable for those with spleen and stomach yang deficiency. Most of the food we eat in our daily lives is neutral, but there are some foods that are hot or cold, such as the warm category: mutton, dog, eel, leek, garlic, ginger, chili, cinnamon, lychee, orange, etc.; the cold category: snapper, mussels, duck, water chestnuts, lotus root, cucumber, watermelon, pear, mung beans, etc.; stagnant gas category: beans, pumpkin, yams, glutinous rice, etc.; easy to produce phlegm and dampness are The general principles of avoiding food are The general principles of avoiding food are: those with hot body or clinical manifestations of heat, such as fever, thirst, cold, red face, red ears, irritability, short urine, dry stool, red tongue with yellow coating, should not eat hot food; those with cold body or clinical manifestations of cold, such as fear of cold, fatigue, light mouth, no thirst, sputum, loose urine and stool, light fat tongue, should not eat cold food; spleen deficiency, stagnant qi, phlegm and dampness People with spleen deficiency, stagnant qi, phlegm and dampness should not eat stagnant qi or greasy food. During radiotherapy and chemotherapy, there is a tendency of gastrointestinal reactions, such as nausea and vomiting, poor appetite and constipation, so light, high-protein, easily digestible food should be the mainstay. Eat more vegetables, fruits and other coarse fiber food, can promote intestinal peristalsis, to prevent constipation. In addition, we should pay attention to a balanced diet, adequate nutrition, that is, under possible conditions to achieve food diversification, meat and vegetables, the appropriate proportion, to avoid partiality and overeating, moderate and stop. Avoid eating pickled, smoked, fried, barbecued, moldy food, and quit smoking and drinking. In short, dietary contraindications should vary from person to person, and should not be implemented blindly. It is recommended that patients should follow the general principle of avoidance of food for dietary adjustment. Malignant tumor is a consumptive disease, so it is important to strengthen nutrition and balanced diet for the recovery of tumor patients. Malnutrition is extremely unfavorable to the recovery of patients. Healthy people need nutrition, and tumor patients need to strengthen nutrition.