Risks

Age
Although colorectal cancer (CRC) can strike at any age, 91 percent of new cases and 94 percent of deaths occur in individuals older than 50. The incidence rate of colorectal cancer is more than 50 times higher in people aged 60-79 than in those younger than 40.

Gender
Colorectal cancer affects both men and women, but overall, CRC incidence and mortality rates are about 35 percent higher in men than in women.

Ethnic background and race
CRC incidence and mortality rates are currently highest in African American men and women. Those of Eastern European Jewish descent currently also have a higher rate of colon cancer than Caucasian men and women. However, because of disproportionate screening, minorities, particularly African Americans and Hispanics, are more likely to be diagnosed with colorectal cancer in advanced stages. As a result, death rates are higher for these populations.

Diet
A diet made up mostly of foods that are high in fat, especially from animal sources, can increase the risk of colorectal cancer. Eating a varied diet, choosing most foods from plant sources, and limiting the intake of foods high in saturated fat will help protect people from developing colorectal cancer.

Exercise
People who are not active have a higher risk of colorectal cancer. Engaging in at least moderate activity for 30 minutes or more on 5 or more days per week will reduce colorectal cancer risk.

Smoking and alcohol
Recent studies show that smokers are 30 percent to 40 percent more likely than nonsmokers to die of colorectal cancer. Moderate to heavy use of alcohol, or 4 or more drinks per week, has also been linked to colorectal cancer.

Personal history of bowel disease
A personal history of colon cancer or intestinal polyps and diseases such as chronic ulcerative colitis, Crohn's disease, and inflammatory bowel disease increase a person's risk of developing colorectal cancer.

Family history/genetic factors
A person who has a specific inherited gene syndrome (such as familial adenomatous polyposis (FAP) or hereditary non-polyposis colon cancer (HNPCC)) is at increased risk for developing colorectal cancer. People with a strong family history of colorectal cancer (defined as cancer or polyps in a first-degree relative-parent or brother or sister-younger than 60 or two first-degree relatives of any age) are also at increased risk for developing colorectal cancer. However, 75 percent of cases occur in people with no family history of colorectal cancer.