To help prevent colorectal cancer, eat plenty of fresh fruits and vegetables; cut back on red meat and other high-fat foods, such as eggs and many dairy products. You can get the protein you need from low-fat dairy products (also a good source of calcium), nuts, beans, lentils, and soybean products. Calcium supplements have also been shown in some trials to modestly reduce the risk of colon cancer. Avoid overcooking or barbecuing meats and fish. Eat a diet rich in cereal fiber or bran and yellow and green vegetables.
Speak with your doctor about the latest evidence on aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) and their effects on colorectal cancer development. Some studies show that people who regularly take aspirin significantly reduce their risk for colorectal cancer, although other studies show no correlation. In any event, don't start taking aspirin on your own; it is a drug and can cause health problems if taken without a doctor's advice. Hormone replacement therapy has been shown to reduce the risk of colon cancer in women. However, it can put them at an increased risk of other cancers.
Being overweight increases the risk of developing colon cancer. Regular physical activity lowers the risk of colon cancer, with those who engage in high levels of activity lowering their risk by as much as 50%.
If you are over 50, make sure that you are being properly screened for colorectal cancer, especially if you are at high risk for the disease. Finding and removing large polyps before they become cancer is the best way to prevent the disease.