In recent years, with the improvement of people’s living standard, the incidence of colorectal cancer is increasing year by year, ranking 4th in the world in terms of cancer incidence and mortality, with a higher incidence in developed countries and urban areas of developing countries. Some scholars have suggested the possible mechanisms for increasing the risk of colorectal cancer by eating meat: (1) heterocyclic amino acids produced during the cooking of lean meat; (2) endogenous nitrite products in the intestinal lumen of the large intestine; (3) the role of iron in oxidation. 2, fatty acids Some scholars have pointed out that the risk of colon cancer is doubled in people with high fat intake than in the lower quintiles. Studies have shown that the risk of colon cancer is slightly increased in people with high quartiles of saturated fat intake. Further studies have also confirmed that fats may have a carcinogenic effect through the generation of oxides and fatty acids. Dietary fiber exists in vegetables, fruits, cereals and other foods, mainly divided into insoluble fiber (such as lignin, cellulose, hemicellulose, etc.) and soluble fiber (including pectin, gum and gum pulp, etc.), which has a certain protective effect on the colonic mucosa. A large number of experiments and epidemiological investigations have been conducted to study the relationship between dietary fiber and colorectal carcinogenesis. Some experts have concluded that various fibers from food and colon cancer risk are negatively correlated, while fibers from vegetables and fruits are strongly correlated with the reduction of colon cancer risk, which is consistent in both men and women, but the negative correlation of wheat fiber is limited to women, while the negative correlation of soy fiber is limited to men. A series of studies have shown that long-term consumption of foods rich in folic acid can reduce the risk of colon cancer. Intermittent intake of high calcium diet can weaken the pro-cell division effect of ionized deoxycholic acid, fatty acid, linoleate and oleate, and daily intake of 1.5-2g of calcium can significantly reduce DNA synthesis of colon mucosal cells in people with high risk of colorectal cancer. 6, alcohol, coffee Studies have found that the mortality rate of sigmoid colon cancer in men who drink alcohol daily is five times that of non-drinkers. 1992-1994 Ontario, Canada, conducted a study on the relationship between coffee and bladder cancer, colon cancer and rectal cancer. The study showed a linear (positive) relationship relative to the risk ratios of 0.9 (95% CI: 0.8-1.1) for those who drank less than 1 cup of coffee per day, 0.8 (95% CI: 0.7-1.0) for those who drank 1 to 2 cups, 0.8 (95% CI: 0.7-1.0) for those who drank 3 to 4 cups, and 0.7 (95% CI: 0.5-0.9) for those who drank 5 or more cups. In an op-ed in the weekly American Journal of Gastroenterology, Dr. Constantine said that caffeine may be the key to coffee’s ability to combat tumors, after counting the caffeine intake of 9,849 volunteers over the past 19 years. It is now more commonly believed that caffeine interacts with anti-tumor cytokines in the body (now thought to be mainly TNF), thereby inhibiting tumor cell DNA synthesis.