Lung cancer is the most common malignant tumor worldwide and also the most prevalent malignant tumor in China, which seriously threatens human health. Patients with lung cancer often go through anti-tumor treatments such as surgery, radiotherapy, chemotherapy, targeted therapy, etc. Due to the disease itself and anti-tumor treatment can cause malnutrition, which can affect anti-tumor treatment, increase adverse reactions, prolong hospitalization and increase morbidity and mortality rate. Therefore, it is important to understand the habits and taboos before and after lung cancer chemotherapy for lung cancer patients’ recovery. Chemotherapy is an important treatment for lung cancer, but it can cause nausea, vomiting, loss of appetite, abdominal distension and diarrhea, thus affecting patients’ feeding and causing malnutrition and weight loss. Common adverse reactions of chemotherapy drugs for lung cancer: 1. Cisplatin is often included in the chemotherapy regimen for lung cancer, and the gastrointestinal reactions caused by cisplatin are often serious, which can cause acute or delayed nausea and vomiting, as well as constipation, abdominal distension, and even intestinal paralysis. 2. The adverse reactions of chemotherapy drugs in other programs are mainly gastrointestinal reactions, bone marrow suppression (that is, reduction of white blood cells and platelets, anemia), joint and muscle pain, allergic reactions, mucositis, etc. Before and after lung cancer chemotherapy: Pre-operative lung cancer patients should be screened and evaluated by nurses or dietitians for nutritional risk during hospitalization, and appropriate nutritional interventions should be made according to malnutrition risk rating. Patients without malnutrition do not need special nutritional treatment and can follow normal dietary arrangement. Patients with mild to moderate malnutrition are advised to adjust their diet or take oral enteral nutrition preparations for supplementation under the guidance of a dietitian. Patients with severe malnutrition should undergo nutritional therapy under the guidance of a dietitian for 1-2 weeks before undergoing surgery, otherwise it is likely to lead to an increased incidence of postoperative infection and delayed wound healing. The dietary principles are high protein, high energy and high vitamin diets. If the energy needs cannot be met by conventional diet, oral supplemental enteral nutrition supplements should be taken. Obese patients should eat a low-energy, high-protein, low-fat diet to properly control their weight and prevent wound healing from being affected by excess body fat after surgery. Patients who choke on water should avoid liquid food or beverages before treatment to reduce the risk of pulmonary infection, and a nasal feeding tube can be placed if necessary. The day before surgery, a light diet should be the main focus and not too much or too full. 2.After lung cancer chemotherapy: It is advisable to resume oral feeding or give oral enteral nutrition supplements as soon as possible after surgery to promote digestion and immune function recovery. Dietary principles: from less to more, gradually from clear liquid food or liquid food, gradually transition to semi-liquid food, meal arrangement should be nutritious, fine, soft and rotten, such as rice soup, batter, lotus root powder, vegetable puree, meat puree, yogurt, egg custard, minced meat porridge, etc. After a period of time, gradually transition to soft food or common meal, avoid spicy and stimulating food. If combined with chronic obstructive pulmonary disease leading to dyspnea, heart tired and tight gas patients need to reduce carbohydrate intake (such as rice, noodles and other staple foods), it is still recommended to choose food or enteral nutrition preparation under the guidance of dietitian! Strengthen lung function exercise and gradually resume physical activity after surgery, avoid prolonged lying! 3.During radiotherapy for lung cancer: there are often dry mouth, poor appetite, nausea and vomiting and other gastrointestinal reactions in the digestive tract, which cause emotional tension, pain and apprehension. First of all, we should eliminate bad psychological factors, especially don’t be nervous before meals, keep emotionally stable, create a good eating environment, and try to eliminate pus and phlegm blood from the potty, spittoon and drug change to avoid malignant stimulation. Patients with advanced lung cancer will have symptoms such as fever, emaciation and weakness, etc. The main psychological reaction in this period is anxiety and depression, which will lead to different degrees of loss of appetite. The diet should be diversified, not partial, and avoid always eating one kind of food. If you feel nauseous when eating, you can chew a few slices of ginger before meals. At the same time, to keep the bowel movement smooth, eat more coarse fiber food, such as asparagus, celery, bananas. The most important thing is not to be too hungry and too full, do not eat sticky and heavy food, so as not to cause loss of appetite.