PREVENTING COLORECTAL CANCER

Colorectal cancer is expected to be the third most commonly diagnosed cancer in Canada in 2020 and approximately 26,900 Canadians will be diagnosed with the disease. The risk of developing colorectal cancer depends on various factors. While you cannot change some risk factors such as age or family cancer history , there are certain things that you can do to help lower your cancer risk.

Reduce your risk for colorectal cancer

Follow cancer screening guidelines

Screening for colorectal cancer means looking for the presence of cancer or pre-cancer in someone who does not show any signs or symptoms of the disease.

Since colorectal cancer almost always develops from precancerous polyps (growths), participating in regular screening can help to find and remove these polyps before they become cancerous. Screening can also help to find colorectal cancer when it is in the early stages, when it has not grown beyond the colon or rectum and there is a better chance of successful treatment. Be sure to talk to your doctor about when you should start regular colorectal cancer screening.

In Canada, colorectal cancer screening begins at 50 years of age for average-risk individuals. Screening is usually done with a stool test every 2 years or a flexible sigmoidoscopy every 10 years. For individuals over the age of 75, talk to your doctor to discuss the most appropriate screening options.

Follow-up for positive stool tests should include either a colonoscopy or flexible sigmoidoscopy.

It is recommended that individuals at high-risk for colorectal cancer undergo more frequent screening and at an earlier age than people at average risk. You may be at a higher risk for colorectal cancer if you have:

A strong family history of colorectal cancer or polyps. Talk to your doctor to find out if you may benefit from genetic counseling to best review your family cancer history and determine the likelihood of having an inherited cancer syndrome
An inflammatory bowel disease (ulcerative colitis or Crohn’s disease)
An inherited cancer syndrome such as Lynch syndrome or familial adenomatous polyposis (FAP)

Be sure to discuss your personal colorectal cancer risk with your doctor to develop an appropriate screening plan.

Lifestyle factors

The recommendations below come from the World Cancer Research Fund and the American Institute for Cancer Research report “Diet, nutrition, physical activity and colorectal cancer” which systematically gathered and analysed global scientific research on the impact of lifestyle factors on colorectal cancer risk.

Diet, body weight and physical activity

There is strong evidence to support that:

1. Eating foods rich in dietary fibre lowers the risk of colorectal cancer. This includes legumes such as beans and lentils, fruits and vegetables, and whole grains.
2. Eating whole grains lowers the risk of colorectal cancer. This includes whole wheat, oats, quinoa, brown rice, popcorn.
3. Consuming processed meats (such as deli meats, ham, sausage, hot dogs, pepperoni) and red meat increases your risk of developing colorectal cancer.
4. Drinking two or more alcoholic drinks every day increases the risk of colorectal cancer.

Take home message: Eating more vegetables, fruits, and whole grains while limiting red and processed meats and alcohol consumption may help lower your risk.

5. Being overweight (BMI: 25.0 – 29,9) or obese (BMI: 30.0 and above) increases the risk of developing colorectal cancer.

Take home message: Maintaining a healthy body weight may help lower your risk.

6. Being physically active lowers the risk of colorectal cancer. 30 minutes of daily moderate to vigorous physical activity is recommended. This could include:

Walking or riding your bike to work
Household chores such as cleaning or yard work

Take home message: Increasing your physical activity levels may help reduce your risk.

For more information about nutrition and healthy living for cancer prevention, visit our Foods that Fight Cancer website.

Quitting smoking

Long-term smoking increases the risk of colorectal cancer and many other cancers. If you smoke and are thinking about quitting, or if you have already quit and need support, see support services by province and territory.

Take home message: Quitting smoking may help reduce your risk.

Last updated: Septembre 2021