Food may be contaminated by certain bacteria, or in the manufacturing process, has added certain preservatives, which contain carcinogenic substances, long-term consumption of such food will increase the chance of cancer. Studies have shown that food contaminated with aflatoxin, water containing nitrite and substances in sauerkraut soup can induce lung cancer. I. Dietary principles for lung cancer patients 1.Congee is the first choice. Lung cancer is a systemic disease that can affect the functions of all organs of the body, and the gastrointestinal tract is no exception. Therefore, lung cancer patients can eat more easily digestible porridge, such as gingko porridge and millet porridge, etc. 2. High-quality protein is indispensable. Lung cancer patients are generally weak, therefore, the daily intake of high-quality protein, such as milk, lean meat, soybean products, fish, eggs, etc., should not be neglected, which not only promotes appetite, but also supplements nutrition. 3, vegetables and fruits can be eaten more. Fresh vegetables and fruits contain a lot of vitamins. Lung cancer patients can eat more tomatoes, oranges, loofahs, strawberries, grapes and green peppers, etc., but they should be in moderation. 4. Eat less and more meals to be healthy. For lung cancer patients, the current medical profession advocates the diet of eating less and more meals, with each meal being 8 minutes full, which is most helpful to health. 2. Dietary taboos of lung cancer 1. Avoid smoking and alcohol. 2. Avoid spicy and stimulating foods: ginger, onion, garlic, cinnamon, chili, leek and pepper, etc. Avoid hot foods such as fried and barbecued foods. 4, avoid greasy, sticky and phlegm-producing food. 5, not easy to eat more sauerkraut, cured meat, pickles.