Understanding Colorectal Cancer

Can I Lower my Risk of Colorectal Cancer? Screening and Prevention

This is the fourth article in the Understanding Colorectal Cancer Guide. This guide was developed by the HealthTree Education Team and last updated and reviewed on April 3rd, 2026. 

Colorectal cancer is one of the most preventable cancers. This is because it usually develops slowly from polyps over many years. Regular screening can find polyps before they become cancerous, and can find cancer early, when it is most treatable.

Colorectal cancer screening

Screening means looking for cancer or pre-cancer before there are any signs or symptoms. For colorectal cancer, screening can find polyps early and remove them before they turn into cancer.

Most guidelines recommend that people at average risk begin regular colorectal cancer screening at age 45. People with a higher risk, such as those with a family history of colorectal cancer or a hereditary syndrome, may need to start earlier or be screened more often. Talk to your doctor about what is right for you.

Which screening test should I choose?

There is no one “best” screening test for everyone. The right option depends on your personal risk, preferences, and access to testing.

• Colonoscopy is the most comprehensive test because it allows doctors to both find and remove polyps during the same procedure, but it requires preparation and sedation.
• Stool-based tests are less invasive and can be done at home, but they need to be done more frequently and require follow-up colonoscopy if results are abnormal.
• Imaging tests like CT colonography are another option for people who cannot or prefer not to have a colonoscopy.

The most important thing is to choose a screening method you are willing and able to complete consistently. Your doctor can help you decide which option is best for you.

Types of colorectal cancer screening tests

Colonoscopy

A colonoscopy lets a doctor see the entire lining of the colon and rectum. They use a flexible, lighted tube with a camera. The doctor can find and remove polyps during the same procedure. If no polyps are found, a colonoscopy typically needs to be repeated only every 10 years.

Stool-based Tests

There are several stool-based tests that can be used to look for colorectal cancer. They look for signs of cancer in your stool. These include:

• Fecal immunochemical test (FIT). This test checks for hidden blood in the stool and is completed every year.
• High-sensitivity guaiac-based fecal occult blood test (gFOBT). This is another stool blood test that is done every year.
• Stool DNA test (such as Cologuard). These tests checks for blood and DNA changes and is done every 1–3 years.

Additional Exams

• CT colonography (virtual colonoscopy). This scan uses X-rays and CT imaging to create pictures of the colon and is completed every 5 years.
• Flexible sigmoidoscopy. This test is similar to colonoscopy but only views the lower part of the colon and is done every 5 years

Reducing your risk of colorectal cancer through lifestyle

While you cannot change all of your risk factors, healthy habits can help lower your risk of colorectal cancer and many other cancers. Changes you can make include:

• Eat a diet rich in fruit, vegetables, and whole grains.
• Limit red meat and avoid processed meats like hot dogs and deli meat.
• Stay physically active by aiming for at least 150 minutes of moderate exercise each week.
• Maintain a healthy weight.
• Limit alcohol consumption and avoid smoking.

Aspirin and colorectal cancer risk reduction

Some studies suggest that regular aspirin use may lower the risk of colorectal cancer in certain groups. However, aspirin also carries risks, including gastrointestinal bleeding. Talk to your doctor before starting or stopping aspirin for cancer prevention.