Chemotherapy is one of the important treatment methods for breast cancer. The common chemotherapy drugs include cyclophosphamide, epi-amycin, 5-fluorouracil, docetaxel, etc. Chemotherapy not only kills cancer cells, but also severely damages normal cells, especially the normal cells that are proliferating, such as epithelial cells, mucous membrane cells of digestive tract and bone marrow hematopoietic cells, etc. It also has a strong effect on the function of important organs, such as liver and kidney. It also has a greater impact on the function of vital organs, such as liver and kidney. As a result, cancer patients often experience serious toxic reactions during radiotherapy, such as gastrointestinal reactions: loss of appetite, nausea, vomiting, mouth ulcers, hair loss, decreased blood count, weakness, and abnormal liver and kidney functions. The occurrence and duration of adverse reactions to chemotherapy are closely related to nutrition. Proper dietary regimen can promote the appetite of patients, increase the intake of nutrients, improve the immunity of the body, reduce chemotherapy reactions, and help patients to safely pass the chemotherapy period. Nutritional requirements during chemotherapy 1. Carbohydrates: Breast cancer patients suffer from poor appetite, nausea, vomiting, diarrhea and other adverse reactions during chemotherapy, which make the intake of carbohydrates decrease, or the digestion and absorption ability is reduced, which leads to lower than the body’s needs. Carbohydrate requirements should account for 60% of the total energy, its supply is mainly based on staple foods, can choose soft rice, porridge, noodles, steamed buns, buns, wontons, etc., do a good job of coarse and fine grains with the variety of varieties. 2. Fat: Since high-fat and high-cholesterol diet will increase the risk of breast cancer recurrence, breast cancer patients should limit the intake of fat and cholesterol. The fat requirement should account for 25% of the total calories, and the daily supply of fat (including fat in main and side dishes and cooking oil) should be about 15~25g, and soybean oil, peanut oil, canola oil, sesame oil, tea oil, olive oil and other fats rich in monounsaturated fatty acids should be used for cooking. 3, protein: protein requirements should account for 15% of the total energy, intake of 1g / (kg.d), of which high-quality protein should be more than 1/3. choose low-fat animal protein such as: chicken, fish, milk eggs, milk, eel, loach is good, and legumes rich in vegetable protein. When eating, pay attention to animal and plant-based collocation, to ensure that the complementary effects of amino acids. 4, vitamins: it is advisable to use red, yellow, green and other dark vegetables and fruits such as: celery, cauliflower, spinach, leeks, garlic moss, carrots and other dates, watermelon, kiwi, apricots, apples, pears, strawberries, etc. 5, dietary fiber: dietary fiber should be 24g daily intake is appropriate, you can use celery, leeks, beets, peas, apples, citrus and other fiber-rich foods. 6. Water: Generally, about 3000ml should be consumed daily, or you can make some green tea to drink. The tea polyphenols in green tea have detoxifying effect and can reduce the toxic effect of chemotherapy drugs on the body. Dietary principles for breast cancer patients 1. The diet should be balanced, no partial food, no taboo food, meat and vegetable, coarse and fine, the more varieties of food the better. 2. To eliminate toxins. Do not eat acidic, salted, moldy, smoked, coloring and flavoring. 3, eat more natural, wild food, eat less artificially reproduced and refined food. 4, reasonable tonic can improve immunity. Certain tonic products such as ginseng, white fungus, red dates, etc. have direct or indirect cancer suppressing and strengthening effects. 5. Use more steam, boil and stew in cooking, and eat less fried and deep-fried food.