REDUCE COLON CANCER RISK BY INCREASING INTAKE OF WHOLE GRAINS AND DECREASING MEAT

The American Institute for Cancer Research (AICR) and the World Cancer Research Fund (WCRF) recently updated information on diet, lifestyle and colon and rectal cancer risk.  Their extensive research review of over 100 studies found there is strong evidence of links between lifestyle and colorectal cancer risk.  An estimated 47% of American’s colorectal cancers, 63,700 cases, could be prevented each year with lifestyle changes. The 2017 report is the first by the AICR/WCRF to conclude there are substantial benefits to eating more whole grains (such as brown rice and 100% whole-grain bread) for reducing colon cancer risk.  Consistent with earlier reviews they found regular physical activity, healthy weight, and not smoking also lower one’s odds of bowel cancers.  Alcohol, meat, and particularly processed meats were found to increase risk of colon and rectal cancer.   

The AICR/WCRF found that three servings (a serving equals 1 slice of bread or ½ cup of cooked grains) a day of whole grains can lower colorectal cancer by 17%.  Other sources of dietary fiber including fruits, vegetables, beans, and nuts, as well as dairy products and calcium supplementation were also deemed beneficial for lowering colon cancer risk.  Besides their fiber, plant foods contain a wide variety of substances that have been linked to lower risk for cancer, including carotenoids, selenium, lycopene and many more.   Fruits and vegetables rich in vitamin C such as strawberries, oranges, and spinach appear to be especially beneficial. Interestingly, regular intake of garlic was also linked to reduced risk.  Exactly how garlic contributes to lower risk is not known but in many laboratory studies, garlic and its components such as allyl sulphur compounds, has shown the ability to slow and stop the formation of colon tumors.   The panel also recommended at least 30 minutes of daily physical activity.   

As for foods to decrease, AICR/WCRF experts advised limiting intake of all red meat, such as beef or pork, to no more than about 17 ounces (i.e. just over 1 pound) per week. The report also stated it is best to eat little or no processed meats such as ham, hot dogs and bacon because frequent intake of these significantly increases the risk of bowel cancer.  Nitrates are added to many processed meats; they contribute to the production of N-nitroso compounds that can damage the lining of the gut.

What to do:  Colorectal cancer is one of the most common cancers, yet this report demonstrates healthy diet and lifestyle substantially lowers risk.  Maintain a healthy weight with a diet rich in whole grains, fruits, and vegetables. Control portions of meat, opting for fish, chicken, or beans more often.  Stay away from processed meats, alcohol, and smoking.  Also get screened.  The USPSTF recommends screening for colorectal cancer using fecal occult blood testing, sigmoidoscopy, or colonoscopy beginning at age 50 and continuing until age 75 years. 

Adapted from articles available at: 

https://medlineplus.gov/news/fullstory_168249.html

https://www.sciencedaily.com/releases/2017/09/170907093623.htm

http://www.aicr.org/learn-more-about-cancer/colorectal-cancer/

Source:

American Institute for Cancer Research and the World Cancer Research Fund International.  Continuous Update Project Report:  Diet, Nutrition, Physical Activity and Colorectal Cancer.  September 7, 2017.  Available at:  https://www.wcrf.org/colorectal-cancer-2017.