Colorectal cancer, which affects people of both sexes, is the third most common form, with 140,000 cases diagnosed each year in the U.S. Incidence of this type of cancer rises significantly after age 50, and it is strongly linked to a history of smoking, obesity, a diet high in sweets, high-glycemic carbohydrates, meat proteins, omega-6 oils, and use of aspartame.

Other risk factors include living a sedentary lifestyle, dysbiosis (bacterial imbalance in the gut), exposure to dietary carcinogens, and having a family history of either colon polyps or cancer.

One of the best recognized associations to colon cancer is having an inflammatory bowel disorder such as Crohn’s disease or ulcerative colitis.

Most cancers, including colon cancer, can remain silent for a considerable amount of time as premalignant changes in tissues occur (in this case, in the colon). Early diagnosis leads to a cure rate of 80 percent to 90 percent. Once colon cancer spreads (called metastasis), the cure rate falls to 5 percent to 10 percent using modern methods.

Especially after age 50, many people can develop small polyps in their colon. The greatest danger comes from having multiple large polyps (called sessile polyps) throughout the colon — a condition that is referred to as Gardner’s syndrome. But just a single sessile polyp can develop into colon cancer.

Gluten sensitivity, a condition that inflames the tissues lining the colon, is also linked to higher incidence of colon cancer.

Colon cancer arises from cells located deep in fissures called crypts. These crypt cells are the repair cells of the colon, but when they are damaged by inflammation, folate deficiency, or carcinogenic chemicals, they become malignant.

We call these precancerous changes aberrant crypt foci. The sessile polyps arise from the abnormal crypts. Once the cells develop into a cancer, they can invade the deeper layers of the colon and eventually get into blood vessels and lymphatics, which then transport the cancer to other parts of the body, most often the liver.