Research has proven that eating more yellow and green vegetables and fruits rich in carotenoids can help prevent lung cancer. A large population-based survey conducted by American researchers showed that people with a low daily intake of vitamin A and carotenoids that can be converted into vitamin A in the body had a significantly higher rate of lung cancer after 10 years. Researchers believe that vitamin A maintains the integrity of the cell nucleus, ensures normal metabolism of epithelial tissue, accelerates nuclear DNA repair, blocks the cellular carcinogenesis process, and inhibits cancer development. Long-term vitamin A deficiency can cause squamous metaplasia in the respiratory epithelium, which can lead to lung cancer. Vitamin A is mainly found in animal tissues, and egg yolk, milk, cream, cod liver oil and animal liver contain more vitamin A. However, these foods are high in cholesterol and calories, so the intake should be careful and not too much should be consumed. Tomatoes, sweet potatoes, carrots, pumpkins, oranges, oranges, mangoes, apricots, amaranth, spinach, leeks, rape, capers, chrysanthemums, peppers and other yellow and green vegetables and fruits are rich in carotenoids and can be eaten in appropriate amounts. Research shows that the trace element selenium can improve the immunity of the body, and insufficient intake of selenium can also increase the risk of lung cancer. Foods such as shrimp, crab, lean meat, eggs, mushrooms and sesame are high in selenium and can be consumed appropriately, but animal foods should not be consumed excessively, otherwise they are not good for cardiovascular health. The main reason for the development of lung cancer is due to long-term smoking, then the primary emphasis of lung cancer prevention is to stay away from cigarettes, not to smoke actively and not to smoke passively. Secondly, when working in toxic and harmful environment, we should do a good job of protection to reduce occupational hazards, avoid indoor smoke and decoration pollution, pay attention to good kitchen ventilation, and stay away from radioactive substances. So we should pay attention to the small details in our daily life to keep diseases away from our health.