Susceptibility factors of colorectal cancer include: increasing age, male, environmental factors, obesity, diabetes, high-fat diet, long-term sitting, insufficient fiber intake, smoking and alcohol abuse, and inflammatory bowel diseases. To prevent and treat colorectal cancer, it is necessary to develop good living habits. The first is to quit smoking and limit alcohol. The burning process of tobacco will produce a lot of toxic and harmful substances, which can induce the occurrence of colorectal cancer, lung cancer and many other malignant tumors. Secondly, weight control and regular physical activity. Secondly, we should pay attention to constipation. Too long stay of feces in the intestinal lumen will increase the contact time between toxins in feces and intestinal mucosa, and cancer will occur. Some people think that oral consumption of aloe vera or drinking tea can improve constipation, in fact, these products can lead to intestinal melanosis due to the accumulation of anthraquinones in the intestinal wall, and intestinal melanosis is one of the culprits of colorectal cancer. In addition, we should pay attention to the regular treatment and close follow-up of diabetes and intestinal inflammatory diseases. (1) Adjust the dietary structure and consume more easily digestible food with high protein, high vitamin and low fat, because fatty diet will raise the concentration of bile acids in the intestine, and high concentration of bile acids has cancer-promoting effect. Fish, lean meat and low-fat dairy products should be used instead of meat with too much animal oil, and cooking methods should be mainly steamed and boiled instead of fried. (2) We should eat more fresh vegetables, fruits and foods rich in trace elements, especially green vegetables rich in vitamin A and C, mushrooms, fungus, shiitake mushrooms and so on. It is recommended to eat oat bran food rich in fiber, which can reduce the stay of carcinogenic substances in the intestinal tract, and to consume honey, yogurt, etc. It has been reported that eating 6 slices of garlic every week can reduce the chance of colorectal cancer. (3) To eat less pickled and smoked foods such as bacon, preserved fish, ham, pickled vegetables, moldy tofu, stinky tofu, etc., or high-temperature grilled and fried foods. Pickled food contains carcinogenic nitrosamines, and high protein food will produce heterocyclic amines after high temperature or deep-frying, all of which have obvious carcinogenic effects.