The evidence that links various foods with the risk of colon cancer is increasing. Fortunately, most of the foods that are good for you are good to eat as well.
So far, there is no surefire way to prevent colon cancer or a recurrence. But increasing knowledge about contributing factors has revealed that lifestyle choices may lower your risk. Some of the information is surprising and may challenge your assumptions. However, much of the new information echoes time-honored common sense: Eat a healthy diet high in fruits and vegetables, maintain an appropriate weight, and exercise regularly. (It also helps a lot if your ancestors didn’t have colorectal cancer.)
Foods to avoid are red meat, charred meat, processed meat, and saturated fat. All are connected with higher cancer risks, though the reason remains unclear. Charred and processed meats have high levels of cancer-promoting chemicals, and saturated fat in red meat may upset the balance of bile acids used for digestion. These foods also contribute to heart disease and other ills.
There is an abundance of good foods. The Mediterranean Diet, which is based on whole grains, fruits, vegetables, fish, and a small amount of meat, is a healthy basis for nutrition.
Fiber is high on the “good” list. It helps to move food through the digestive system and may increase some chemicals known to protect the colon. Studies have generally linked high levels of dietary fiber with low rates of colon cancer and adenomatous polyps, although one recent mega-study did not confirm this. The jury remains out, but for many reasons it’s still good to add fiber (beans, whole grains, fruits, and vegetables) to your diet.
Folic acid -- also known as folate -- is related to a 20–50% lower risk of colon cancer and polyps. It can also offset some effects of alcohol, which inhibits folate production in the body. There is evidence that taking folic acid in a daily multivitamin for five years lowers the risk of colon cancer by almost 50% among women with a family history of colon cancer. All of the sources of dietary fiber listed above contain some folic acid, and you can take it in supplements as well.
Vitamin D and calcium may reduce risks. Higher levels of vitamin D are connected with lower colorectal cancer rates, and calcium in food may lower risks. However, when taken as a supplement, calcium does not appear to have the same effect. Up the odds of lowering your risks by eating calcium-rich dark green vegetables and getting vitamin D in fish, yogurt, milk, and a small amount of daily sunshine.
Other good foods linked with lower colon cancer risks include olive oil, garlic, turmeric, and colorful fruits and vegetables, which are high in antioxidants. The evidence is mixed for coffee, but a moderate amount may reduce risks of both liver and colon cancer.
