Colorectal Cancer

A risk factor for colorectal cancer is something that increases your chance of getting this cancer. Having one or more of these risk factors can make it more likely that you will get colorectal cancer. But it doesn't mean that you will definitely get it. And many people who get colorectal cancer don't have any of these risk factors.

Risks you can't change

Your age

Everyone who is older than 50 has a risk of getting colorectal cancer. And the older you are, the greater the risk. Most cases of colorectal cancer are diagnosed in people older than 50. Most people who get colorectal cancer have no other risk factors besides being older than 50.

Your race and ethnicity

African Americans are at greater risk of getting colorectal cancer (and dying from it) than non-Hispanic whites. And non-Hispanic white people have a higher risk than other major racial or ethnic groups, such as Hispanics, Asians, and Pacific Islanders.^{Reference 2}

Ashkenazi Jews (Jewish people whose ancestors came from Eastern Europe) who have inherited certain genes are also at a higher risk for getting colorectal cancer.^{Reference 3}

Your family's medical history

You are more likely to get colorectal cancer if one of your parents, brothers, sisters, or children has had the disease. This is considered a strong family history. Your risk depends on how old your family member was when he or she was diagnosed and on how many members of your family have had the disease.

You have a very strong family history if all of the following are true:

• You have at least three relatives who have had colon cancer, endometrial cancer, or another HNPCC-related cancer, and at least one of the relatives is a parent, brother, or sister.
• Those relatives are spread over two generations in a row (for example, a grandparent and a parent).
• One of those relatives had cancer before age 50.

If you have a very strong family history of colorectal and related cancers, you may want to have Reference genetic testing. Related cancers include ovarian cancer, stomach cancer, liver cancer, or cancer of the small bowel, among others. Genetic testing is done with a blood test that looks for changed genes (mutations).

The most common gene changes occur in two conditions: Reference familial adenomatous polyposis (FAP) Opens New Window and Lynch syndrome, also called Reference hereditary nonpolyposis colon cancer (HNPCC) Opens New Window. Many people with these changed genes will develop colorectal cancer if they are not carefully watched. Genetic testing can tell you whether you carry a changed, or mutated, gene that can cause FAP or HNPCC.

Your medical history

Your chances of getting colorectal cancer are higher if you have had:

• Colorectal cancer in the past.
• Another type of cancer, such as Reference cancer of the ovary Opens New Window or Reference cancer of the endometrium Opens New Window.
• Reference Polyps removed from your colon, especially if you had large polyps or a large number of polyps.
• Reference Ulcerative colitis Opens New Window or Reference Crohn's disease Opens New Window for more than 10 years.
• Radiation therapy in your abdomen or pelvis.

Lifestyle changes to reduce your risk

• Have a screening test for colorectal cancer. Talk to your doctor about when to start and what test would be best for you.
• Keep a healthy Reference body mass index (BMI) Opens New Window.
• Be physically active with regular exercise.
• Eat more whole grains, fruits, vegetables, poultry, and fish.
• Drink less than 2 alcohol drinks a day.^{Reference 2}
• Quit smoking, if you smoke.

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This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Reference Terms of Use. Reference How this information was developed to help you make better health decisions.