1.Chinese medicine cognition of radiotherapy Chinese medicine believes that radiation is a kind of “fire evil” and “heat poison”, which is most likely to harm yin and consume qi and fluids, causing yin and fluids deficiency and yin deficiency and fire exuberance. The common symptoms are emaciation, dry mouth and throat, thirst for cold, dry cough with little phlegm, or even blood in the phlegm, hoarseness, hot flashes and night sweats, hunger and lack of desire to eat, vague pain in the stomach, occasional nausea, dry stools, dark and short urine, red tongue with little moss (or no moss, tongue like a mirror). 2, dietary contraindications The term “contraindication” in Chinese medicine refers to food or drugs that should not be taken because of the antagonistic relationship with the body and the disease (Chinese medicine pathology), which should be considered comprehensively on the basis of the cold, heat, deficiency and real properties of the disease, combined with the nature and taste of food. It is generally believed that spicy and dry stimulating foods, such as chili, raw onion, ginger, garlic, pepper, mustard, cinnamon, dog meat, donkey meat, leek, etc., should not be taken during radiotherapy because they are most likely to hurt yin and aggravate the disease; warm tonic products, such as ginseng and deer antler, should also be avoided. During radiotherapy, it is advisable to eat more cool and moist vegetables, fruits and other foods, such as cucumber, winter melon, lily, spinach, shiitake mushrooms, silver fungus, lotus root, white radish, water chestnut, pear, apple, watermelon and so on. It is important to note that the intake of such foods should not be excessive, as a large amount of cold food can easily damage the stomach qi and affect the function of the spleen and stomach. Chinese medicine places great emphasis on “protecting the stomach qi”, and medication and diet must follow this principle. During radiotherapy, you can choose to drink Chinese herbal medicine as tea to benefit the qi and nourish the yin to reduce the side effects of radiotherapy. Commonly used drugs include rhizome, white foxglove, prunus, maitake, sage, dendrobium, lily, chrysanthemum, etc. Observation of nail marks can assist in judging the physical deficiency and guiding the dietary contraindications. Generally speaking, if the number of nail marks is 7 or more, the body constitution is hot and easily inflamed, so be careful or avoid eating spicy and stimulating food; if the number of nail marks is 4 or less, the body constitution is cold, so be careful or avoid eating raw and cold food. American ginseng is cooling in nature and has the effect of benefiting qi and nourishing yin, clearing heat and generating body fluid, which is more suitable for use during radiotherapy. The method is easy and effective to take western ginseng tablets. Different parts of the tumor radiotherapy process will show different complications, such as chest tumor prone to radiation pneumonia, radiation esophagitis. Radiation esophagitis is characterized by congestion and edema of the esophageal mucosa, and in severe cases, mucosal ulcers and pain behind the sternum when swallowing can occur. Radiation pneumonia can be seen as fever, wheezing, dry mouth and throat, and dry cough with little sputum. The above manifestations are mostly heat and toxicity, and the diet should be based on foods that have the effect of clearing the lungs and dissolving phlegm and toxicity. You can use pear juice, sugar cane juice, fresh root juice, water chestnut juice and other mixed drinks; you can also often take porridge food, adding sage, lily, red beans, silver fungus, coix seeds, yam, etc. For those who are weak in qi, it is appropriate to add ham (Jinhua ham), cough obviously add Chuan Bai Mu, sleep disturbance add lotus seeds, sesame. Commonly used classical dietary recipes, such as ice sugar lily and lotus seed gingko soup, jujube glutinous rice and red bean porridge, Buddha’s hand porridge, etc. In general, patients should have a light and spicy diet during radiotherapy, and should eat less and more meals. The specific requirements of avoiding food for tumor patients vary from disease to disease, from person to person, and from treatment to treatment method. Please consult your specialist for specific dietary guidance and therapeutic methods. Do not follow harsh dietary requirements that are not scientifically based out of concern for the avoidance of food. Do not take into consideration or listen to the fictitious claims and practices of some cancer patients in terms of diet. In clinical practice, some patients are afraid to eat eggs, tofu and vegetables because of the taboo, and their nutritional status is deteriorating, which is very detrimental to treatment and recovery.