Colorectal Cancer Overview

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Causes, Risk Factors, and Prevention TOPICS

What are the risk factors for colorectal cancer?

While we do not know the exact cause of most colorectal cancers, there are certain known risk factors. A risk factor is something that affects a person's chance of getting a disease. Some risk factors, like smoking, can be controlled. Others, such as a person's age, can't be changed.

But risk factors don't tell us everything. Having a risk factor, or even several, does not mean that you will get the disease. And some people who get colorectal cancer may not have any known risk factors. Even if a person with colorectal cancer has a risk factor, it is often very hard to know what part that risk factor may have played in the development of the disease.

Researchers have found some risk factors that may increase a person's chance of getting polyps or colorectal cancer.

Risk factors you cannot change

  • Age: your risk gets higher as you get older
  • Having had colorectal cancer or certain kinds of polyps before
  • Having a history of ulcerative colitis or Crohn’s disease
  • Family history of colorectal cancer
  • Race or ethnic background, such as being African American or Ashkenazi
  • Type 2 diabetes
  • Certain family syndromes, like familial adenomatous polyposis (FAP) or hereditary non-polyposis colon cancer (HNPCC, also called Lynch syndrome)

Risk factors linked to things you do

Some lifestyle-related factors have been linked to an higher risk of colorectal cancer.

  • Certain types of diets: a diet that is high in red meats (beef, lamb, or liver) and processed meats (like hot dogs, bologna, and lunch meat) can increase your colorectal cancer risk. Cooking meats at very high heat (frying, broiling, or grilling) can create chemicals that might increase cancer risk.
  • Lack of exercise
  • Being very overweight (or obese)
  • Smoking
  • Heavy alcohol use

For more information about risk factors for colorectal cancer, see our more detailed document Colorectal Cancer.


Last Medical Review: 08/15/2013
Last Revised: 01/31/2014