Don't underestimate these humble staple foods like noodles and potatoes, as they are also highly beneficial for preventing disease. A recent study from the University of Cambridge in the UK shows that eating starch-rich foods, such as bananas and cooked potatoes, can reduce the risk of bowel cancer. The study found that China's starch consumption is the highest in the world, more than double that of the UK, while its incidence of colon cancer is half that of the UK.
So, how do starchy foods help prevent colon cancer? When starch enters the colon, bacteria in the colon break it down. During this process, starch accelerates the expulsion of waste products that could cause bowel cancer from the digestive tract. Starchy foods are often rich in potassium, which plays a crucial role in maintaining the excitability of intestinal nerves and muscles, promoting smooth bowel movements and helping to prevent and treat colon cancer. Secondly, some starchy foods, after fermentation, such as vinegar, douchi (fermented black beans), and steamed yeast breads, have increased levels of immunologically active substances like B vitamins, which help maintain the balance of the gut microbiota and clear carcinogens. Moreover, when starch is acted upon by fermentation enzymes in the intestine, it produces large amounts of butyrate. Experiments have already proven that butyrate is an effective inhibitor of cancer cell growth; it can directly inhibit the proliferation of大肠 bacteria (E. coli) and prevent the formation of potentially cancerous cells in the intestinal wall.
Therefore, in daily diets, people should pay attention to consuming more starchy foods, ensuring that every meal includes a starchy item. Generally, the total daily intake of starchy foods should account for 50%-60% of the total daily energy. In addition to common carbohydrate-rich staples like rice, corn, and wheat, and root vegetables like potatoes, Chinese yams, and sweet potatoes, people should also supplement with more beans and starchy fruits like bananas and pitaya. It is recommended to frequently consume healthier starchy foods, mainly the following: steamed white sweet potatoes, steamed Chinese yams, steamed pumpkin, whole wheat bread, oatmeal, boiled corn, jujube porridge, douchi, etc. Of course, some starchy foods can be unhealthy if eaten in excess and should be consumed as little as possible, such as french fries, potato chips, pastries high in margarine, and various refined grain snacks.