The route to avoiding colon cancer is to eat plenty of fiber, right? Not necessarily. Modern researchers are not so sure that the decades-old belief is valid after all. Nevertheless, fiber has other benefits that make it an important component of a healthy diet.
Definition
Fiber is "a type of carbohydrate the body can't digest," according to the Harvard School of Public Health. Sources of fiber include fruits, vegetables, whole grain breads and various types of beans. Some fiber is soluble in water, and some is not. Dietary fiber appears to protect against diabetes, heart disease and diverticular disease, and it can also prevent constipation, according to the Harvard School of Public Health. For optimal health, children and adults should get at least 20 grams of fiber per day from food, according to Harvard.
Theory
Researchers have proposed various hypotheses for how fiber might help reduce the odds of developing colon cancer. Among them, according to the Physicians Committee for Responsible Medicine, which advocates a vegan diet, is that it "moves food more quickly through the intestines, helping to eliminate carcinogens." It also "draws water into the digestive tract," according to the group, which combines with fiber to "make fecal matter bulkier, so carcinogens are diluted."
History
The notion that fiber protects against colon cancer dates back to the 1970s, according to the Harvard School of Public Health. The recommendation to consume large amounts of it, according to Harvard, stemmed from observations that colon cancer rates were low in countries that followed this dietary pattern. But nowadays, the school said in an article posted in 2010, scientists and doctors have "strong evidence that fiber intake has no direct link with colon cancer." The Harvard article noted: "Further studies might yet demonstrate a weak effect of fiber on colon cancer, although such a finding wouldn't alter the conclusion that other means must be sought to prevent colon cancer."
Insight
The debate may not be over yet. The true issue may be more nuanced than whether more fiber simply is--or is not--better, according to research published in 2007 in the American Journal of Clinical Nutrition. The study by researchers at the National Institutes of Health suggests that whole grain fiber, but not fiber from other food sources such as white bread and processed breakfast cereals, reduces your colon cancer risk. The group of study participants with the highest whole grain intake had a 20 percent lower risk of colorectal cancer than participants who consumed the least.
Prevention/Solution
A key to preventing colon cancer is regular screening, according to the Mayo Clinic. For people at average risk of developing the malignancy, screening should start at age 50. People at higher risk may need to start earlier, depending on their doctor's recommendations. Available screening methods, according to the Mayo Clinic, include annual fecal occult blood testing; flexible sigmoidoscopy every five years; double-contrast barium enema every five years; colonoscopy every 10 years; virtual colonoscopy (CT colonography) every five years; and stool DNA testing. Additionally, the clinic says fruits, vegetables and whole grains "contain vitamins, minerals, fiber and antioxidants, which may play a role in cancer prevention." It also advises drinking alcohol in moderation if at all, exercising most days of the week, avoiding tobacco use and maintaining a healthy weight.
