The most important way that you can reduce your risk for getting colon or rectal cancer—or dying from it—is to have a good personal screening plan and follow it!
Lifestyle changes can also reduce the risk for colon and rectal cancer and adenomatous polyps that can lead to cancer. But, while it can be helpful, healthy lifestyle cannot replace the need for colorectal cancer screening.
After studying all the current evidence for preventing cancer, the American Institute for Cancer Research (AICR), in collaboration with the World Cancer Research Fund issued Food, Nutrition, Physical Activity and the Prevention of Cancer in 2007. The following are recommendations from their expert panel for reducing your chances of getting colorectal cancer.
There is convincing evidence that the following strategies can decrease colorectal cancer risk.
- Don’t smoke. If you do smoke, stop.
- Increase your physical activity.
- Maintain a health body weight. Avoid overall body fat, especially fat around your waist.
- Reduce how much red meat and processed meats you eat.
- Use alcohol in moderation if you are male.
There is probable evidence that these additional strategies can reduce risk.
- Increase foods that contain dietary fiber.
- Include garlic in your diet.
- Drink more milk if you can tolerate it.
- Add foods with calcium.
- Use alcohol in moderation if you are a woman.
In addition, there is some suggestive evidence that non-starchy vegetables, fruits, foods that contain folate or selenium, fish, and foods containing vitamin D may reduce risk. Foods containing iron, cheese, animal fats, and sugary food may increase the possibility you will get colorectal cancer.
Many studies have linked smoking to colon and rectal cancer. Current smokers double their chance for colorectal cancer, former smokers have about a 50 percent increase in risk.
There is also some evidence that secondhand smoke, particularly during childhood, increases risk for colorectal cancer.
AICR recommends at least 30 minutes of moderate physical activity each day at the level of a brisk walk. Aim to increase each day’s exercise to 60 minutes. Walking, swimming, housework, biking, and dancing all count. Short ten to fifteen minute periods of activity also count toward your daily goal. Exercise experts point out that choosing an activity that is fun for you increases the chance you’ll continue to do it.
Be sure to check with your doctor before beginning a new or increased exercise program.
Body Mass Index or BMI is a measure of body fat based on adult height and weight. Normal BMI ranges from 18.5 to 24.9, overweight BMI is 25.0 to 29.9. Anything 30.0 and over represents obesity.
Abdominal fat that gathers around the waist is particularly dangerous. Waist circumference should not exceed hip measurements.
For women, obesity has overtaken smoking as a risk factor for advanced polyps and colorectal cancer.
Risk associated with red meat—beef, pork, lamb—begins at about 18 ounces a week. Keep servings of red meat to about 3 ounces each or the size of a deck of cards.
Even small servings of processed meats increase colorectal cancer risk. Processing includes curing, smoking, salting, or using chemical preservatives. Avoid bacon, ham, sausage, salami, and hot dogs or save them for special, rare occasions.
Cooking meat at high temperatures or over open flames increases their cancer-causing ability. Avoid grilling. If you do cook over a flame, use lean meats without fat, marinate them, and remove charred sections before eating. Flipping a burger several times can reduce—but not eliminate—risk by lowering cooking temperature.
Men have a greater risk from alcoholic beverages, but women are also affected. Recommendations are that women should have no more than one drink a day, men no more than two.
Evidence of the role of fiber in preventing colon and rectal cancer varies, but eating more food with fiber probably reduces colorectal cancer. Aim for 30 grams of fiber a day, and be sure to drink water and other liquids with it.
Eating at least 5 servings a day of vegetables and fruits, and at least seven servings of beans and whole grains, will generally ensure you are getting enough dietary fiber.
Studies have found connections between use of aspirin or nonsteroidal antiinflammatory drugs (NSAIDS) and fewer colorectal polyps. However, use of these drugs may have other health consequences including GI bleeding and increased risk for heart attack and stroke. Balancing risks for colorectal cancer and other health problems needs to be discussed with your doctor.
The Sunshine Connection
Sunlight helps the body to produce vitamin D and there is evidence that higher levels of vitamin D in the blood leads to fewer colon polyps and less colorectal cancer. Colon cancer rates are higher in areas with little sunshine.
However, it is difficult to get adequate vitamin D from sun alone, particularly if you are dark-skinned or live in a cold climate. Vitamin D supplements, along with 15 to 20 minutes in the sun each day, may help. Be sure to tell your doctors about any supplements you take. Discuss the daily dose of vitamin D you will need to maintain a healthy blood level.
Research is underway to understand the role of supplements including calcium, vitamin D, selenium, and folate to prevent both polyps and cancer. Meanwhile, recommendations are that you get these nutrients from food. Again, always tell your doctors about supplements you are taking.
Where Can You Go for More Information?
A summary of the full AICR – World Cancer Research Fund 2007 Report discusses how the report was developed and lists recommendations for overall cancer prevention. The entire report can be purchased from AICR.
Aim for a Healthy Weight, developed by the NIH National Heart, Lung, and Blood Institute, can help you calculate your BMI and manage your weight.
Information from the American College of Gastroenterology about the GI dangers of aspirin and NSAIDS.
Dietary Supplement Fact Sheet — Vitamin D from the National Institutes of Health.