Age: Your chance of having colorectal cancer goes up after age 50. More than 9 out of 10 people found to
have colorectal cancer are older than 50.
Having had colorectal cancer before: Even if a colorectal cancer has been completely removed, new cancers
could start in other areas of your colon and rectum.
Having a history of polyps: Some types of polyps increase the risk of colorectal cancer, especially if they are
large or if there are many of them.
Having a history of bowel disease: Two diseases called ulcerative colitis and Crohn’s disease increase the risk
of colon cancer. In these diseases, the colon is inflamed over a long period of time and there may be ulcers in
its lining. If you have either of these, you should start being tested at a young age and have the tests often.
Family history of colorectal cancer: If you have close relatives who have had this cancer, your risk is increased.
This is especially true if the family member got cancer before age 60. People with a family history of colorectal
cancer should talk to their doctors about how often to have screening tests.
Certain family syndromes: A syndrome is a group of symptoms. For example, in some families, members tend to
get a type of syndrome that involves having hundreds of polyps in their colon or rectum. Cancer often develops
in one or more of these polyps.
If your doctor tells you that you have a condition that makes you or your family members more likely to get colorectal
cancer, you will probably need to begin colon cancer testing at a younger age and you might think about
genetic counseling.
Ethnic background: Jews of Eastern European descent (Ashkenazi Jews) have a higher rate of colon cancer.
Diet: A diet high in fat, especially fat from animal sources, can increase the risk of colorectal cancer.
Lack of exercise: People who are not active have a higher risk of colorectal cancer.
Overweight: Being very overweight increases a person’s colorectal cancer risk.
Smoking: Most people know that smoking causes lung cancer, but recent studies show that smokers are 30% to
40% more likely than nonsmokers to die of colorectal cancer. And smoking increases the risk of many other cancers
as well.
Alcohol: Heavy use of alcohol has been linked to colorectal cancer.
Even though we don’t know exactly what causes colorectal cancer,
there are some steps you can take to reduce your risk.
Screening tests: First, you should follow the early detection screening guidelines mentioned below to help find
colon or rectal cancer. When these cancers are found and treated early, they can often be cured. Screening can
also find polyps. Removing these polyps helps prevent some cancers.
People who have a history of colorectal cancer in their family should check with their doctor for advice about
screening tests or other tests to find cancer early.
Diet and exercise: The American Cancer Society recommends choosing most of your foods from plant sources,
eating at least 5 servings of fruits and vegetables every day and limiting the amount of high-fat foods you eat.
Some studies suggest that taking a daily multivitamin containing folic acid or folate can lower colorectal cancer
risk. Other studies suggest that getting more calcium can help. Getting enough exercise is important as well.
The American Cancer Society recommends at least 30 minutes of physical activity on 5 or more days of the
week.
Aspirin and other drugs: Aspirin appears to prevent the growth of polyps. A drug called Celebrex also reduces
polyps for some people whose family members tend to develop polyps. But these medicines can have side
effects. For this reason, experts do not advise the general public to take them to try to prevent colorectal cancer.
If you are at high risk for colorectal cancer, talk to your doctor about what you should do.
Other factors: People with a family history of colorectal cancer may benefit from starting screening tests when
they are younger and having them done more often than people without this risk factor.
