The high incidence of colorectal cancer in economically developed regions is mainly related to their dietary structure, which is called “Western cultural diet”. This diet is high in animal protein, high in fat, and too fine, such as beef, less fiber and refined rice and noodles. This is mainly because the fat and its decomposition products in food may have carcinogenic or synergistic carcinogenic effects. Too little fiber intake can reduce the amount of feces and make the feces pass through the intestinal tract for a significantly longer period of time, resulting in a higher concentration of synergistic carcinogens in the feces and a significantly longer contact time with the colonic mucosa, and long-term contact between carcinogens and the colonic mucosa may lead to carcinogenesis. Therefore, we advocate eating more vegetables and fruits containing more fiber, such as spinach, celery, fruits, etc., to keep the stool smooth and reduce the contact time between carcinogens in stool and colon mucosa, and reduce the intake of fat and animal protein in food, which can reduce the production of carcinogens and carcinogenic effects of their decomposition products, so as to reduce the potential risk of colon cancer development. If you happen to have a diet structure with excessive intake of high-fat foods such as meat and little intake of coarse fiber foods such as cereals and vegetables, plus little exercise, you definitely belong to the susceptible group of colorectal cancer. Although constipation is not directly related to bowel cancer, it can play a role in contributing to it. Because feces contains a carcinogen, medically known as “secondary bile acid”, and constipated people have more “secondary bile acid” in the intestinal cavity, which is likely to induce intestinal cancer if the mucous membrane is constantly stimulated for a long time. Therefore, to develop the habit of regular bowel movement and prevent constipation can prevent intestinal cancer. Especially, we should emphasize the habit of regular defecation in the early morning, even if there is no intention to go to the toilet in the morning, after which a conditioned reflex will be formed slowly. The reason for choosing early morning for defecation is that after a night’s rest, when the body position changes after waking up, the colon peristalsis is accelerated when the intestine changes from the original lying state to the upright state, which is the best time for defecation and the easiest to defecate. If you delay or do not care about the signal of defecation, after a long time there is no signal to go to the toilet, resulting in the formation of constipation, and the retention of overnight stool will not only release toxins, but also repeatedly absorb intestinal water, so that the fecal mass becomes more dry and hard, prolonging the time that stool stays in the intestine, which in turn induces inflammatory reactions, necrosis, and ultimately may lead to cancer.