Why is there such a rapid increase in the incidence of colorectal cancer? The familiar explanation is the westernization of lifestyle. What kind of “westernized life” causes colorectal cancer? The familiar explanation is a high protein, high fat, low grain, low fruit and vegetable diet. Colorectal cancer is a combination of colon and rectal cancer In Shanghai, colorectal cancer is also called “cancer second”, meaning that colorectal cancer is the second most prevalent tumor. At the beginning of this century, colorectal cancer was the third most prevalent cancer in Shanghai, and in just ten years, it has replaced stomach cancer as the second most prevalent cancer. Nationwide, colorectal cancer is still in fifth place, but its growth rate is strong. Why has the incidence of colorectal cancer increased at such a rapid rate? The familiar explanation is the westernization of lifestyle. What kind of “westernized life” leads to colorectal cancer? The familiar explanation is a high protein, high fat, low grain, low fruit and vegetable diet. Why does such a lifestyle lead to colorectal cancer? There are not many detailed explanations, so this article is to analyze this issue from the physiological perspective. Watch out for a danger signal: eating too well and farting Under the traditional diet, after the food is digested and absorbed, it enters the large intestine through the small intestine, the protein and fat residues are small, and these small residues can continue to synthesize essential substances such as B vitamins, vitamin K and some non-essential amino acids under the action of intestinal flora, which are all beneficial to health. However, if the intake of animal proteins and fats increases too much beyond the capacity of the small intestine to digest and absorb, what enters the large intestine will no longer be a small amount of residue. In the large intestine, the “fermenter”, too much nutrients will lead to dysbiosis, and those surplus nutrients will be synthesized into a large number of amines, amines are carcinogens. Amines, either as a liquid or as a volatile gas, are very smelly. So, there are times when people eat too much and too well, and their intestines are overburdened and they fart badly. Stinky farts are not only embarrassing, they are also a red flag. Dietary fiber: the intestinal flora and toxins “packed” into the feces of the credit Westernized diet in addition to more protein, more fat, another drawback is that less dietary fiber. Dietary fiber is a concept that is somewhat unfamiliar to people. Dietary fiber did not appear in nutrition before 1970, and it is a concept that has been taken seriously in recent decades. Dietary fiber is a food nutrient that is generally not easily digested and comes primarily from the cell walls of plants. Dietary fiber plays an important role in maintaining healthy digestive function by cleaning the digestive wall and enhancing digestion, while diluting and accelerating the removal of carcinogens and toxic substances from food. Dietary fiber is mainly derived from grains, legumes, vegetables and fruits, but in the westernized diet, most people have reduced their intake of grains and the amount of dietary fiber in food has been greatly reduced. Dietary fiber cannot be digested and absorbed in the small intestine; it enters the large intestine with food residues and is eventually excreted from the body. However, do not underestimate these “dregs” can not be absorbed, they are much more valuable than the excessive “essence” of the residue. Dietary fiber plays the role of a “scavenger” in the colon: it absorbs a lot of water, expands and enlarges, “packing” necrotic cells, excess intestinal flora and toxins into the stool along the way, and stimulates intestinal peristalsis to promote bowel movement. How can I tell the health status from my stool? Ideally, if the absolute and relative proportion of dietary fiber in the food is sufficient, the stool volume will appear to be very large, and may even be much larger in volume than the total volume of food consumed. Such a stool is a healthy stool, usually semi-solid, containing more than 80% of water, and carrying out more than one-third of the dry weight of the stool in terms of intestinal waste. These people have very smooth bowel movements and not only have a very low incidence of colorectal cancer, but also a low incidence of cardiovascular disease and diabetes.