The large intestine includes the colon and the rectum. The major function of the large intestine is to reabsorb water so that the body can rid itself of solid waste. Colorectal cancer occurs when malignant cells infiltrate the inner lining of the colon and/or rectum. The National Cancer Institute reports that 51,370 Americans died of colorectal cancer in 2010. While colorectal cancer is the second leading cancer killer of both males and females in the United States, it is also one of the most preventable types of cancer.
Colorectal Cancer Screening
Since colorectal cancer is largely preventable, screening is crucial, according to the American College of Gastroenterology. During a colorectal screening, your physician will look for cancer or polyps that need to be removed, which can dramatically improve your survival rate. High-risk individuals include those with a personal history of colorectal cancer or polyps, a strong family history, or predisposing chronic digestive conditions such as Crohn's disease or ulcerative colitis. ACG recommends a baseline colonscopy at age 50, age 45 for African Americans, and then every 10 years after for healthy, normal-risk individuals. For high-risk individuals, screening type and frequency varies according to your physician's recommendation.
Lifestyle Related Risk Factors
NCI reports that there are several lifestyle related risk factors to consider. Obesity and lack of physical activity are both linked to an increased risk of colorectal cancer, as is consuming a high-fat, meat-based diet. Smoking is linked to an increased risk of both cancerous and noncancerous colorectal tumors, and drinking alcohol may also increase your risk. NCI recommends a low-fat, high-fiber diet rich in fruits and vegetables to lower your overall cancer risk. Cruciferous vegetables and foods high in folate and calcium may be particularly important in colorectal cancer prevention.
Cruciferous Vegetables
Cruciferous vegetables include broccoli, brussels sprouts, cabbage, cauliflower, collard greens, kale, kohlrabi, mustard, rutabaga, turnips, bok choy, Chinese cabbage, arugula, horse radish, radish, wasabi, and watercress. Jane Higdon, Ph.D., of the Linus Pauling Institute, reports that cruciferous vegetables may help your body rid itself of dietary carcinogens such as those found in well-cooked meat. The NCI does not have specific dietary intake recommendations for cruciferous vegetables, but Higdon reports that consuming at least five servings per week may be beneficial. One serving is equivalent to one-half cup cooked or one cup raw.
Folate
Folate is a water-soluble B vitamin naturally found in food that is important in DNA synthesis and repair. Folate deficiency is thought to cause DNA damage that can increase your colon cancer risk, according to the National Institutes of Health. NIH reports that women and men who consume the recommended daily intake, 400 micrograms per day, of folate seem to have lower risk of colon cancer. NIH advises against folic acid supplements to prevent cancer and instead encourages increased intake of folate-containing foods. Some good sources of folate are fortified breakfast cereals, beef liver, green leafy vegetables, dried beans, peas and oranges.
Calcium
According to the Dairy Council of California, calcium may decrease your risk of colon cancer. The exact mechanism is unknown but may be related to the ability of calcium to bind to cancer-causing agents in your body, allowing them to be excreted. The Dairy Council reports that 1,200 to 1,500 mg of calcium per day seems to be the most protective. You can reach your calcium goal by consuming three to four servings of low-fat dairy products daily. Skim or 1 percent milk, low-fat yogurt and low-fat cheese are great sources of calcium.
References
- National Cancer Institute: Colon and Rectal Cancer
- American College of Gastroenterology: Colorectal Cancer Screening
- National Cancer Institute: Colorectal Cancer Prevention
- National Institutes of Health: Dietary Supplement Fact Sheet -- Folate
- The Dairy Council of California: Cancer Risk and Dairy-Product Consumption
- Linus Pauling Institute at Oregon State University: Cruciferous Vegetables
