Published on February 17, 2026

the word colonoscopy on paper with check box and pen

How to Prevent Colon Cancer

Not all cancers can be prevented – but colon cancer is an example of a disease that can be stopped if it’s caught early.

Colon screening and lifestyle modifications can stop this life-threatening disease. In fact, a colonoscopy can detect polyps that are at precancerous stages.

Mara Hermiston, DO, Chief Medical Officer for Avera Medical Group, explains how you can stop this common cancer before it even starts.

Polyp Removal Is Key for Prevention

Colon screening is recommended starting at age 45 for both men and women. Colonoscopy remains the best way to prevent colon cancer because it goes beyond detection. Precancerous polyps can actually be removed during the procedure.

“This means we can remove the polyp before cancer starts developing in the first place, Hermiston said. “Other methods of detection can spot the disease, but they don’t allow for that immediate removal.”

These polyps typically develop with no symptoms, which makes screening even more important. Symptoms such as blood in the stool, bowel changes or bloating often occur after cancer has developed and in a later stage, making it harder to treat, Hermiston said.

Get Screened for Colon Cancer

Schedule your colonoscopy or learn more about screening and colon cancer.

Can Food Prevent Colon Cancer?

It’s hard to say if weight management, food and exercise can stop cancer. It’s proven to reduce the risk of many types, including colon cancer. Experts recommend a high-fiber and low-fat diet for healthy colon function. This includes fresh fruits and vegetables, beans and whole grains.

Added sugar and processed foods also should be limited, according to research.

Cancer Prevention Means Ongoing Colon Screening

If your doctor removes polyps during a colonoscopy screening, new ones could grow over time. Additional colonoscopies allow your doctor to screen and remove the new polyps as they develop.

Most people will need a colonoscopy once every 10 years until age 75. Your doctor will recommend what’s best for you. Family history of colorectal cancer or a personal history of precancerous polyps may call for more frequent follow-ups.

“When you’re in for your annual exam, talk to your provider about screenings you should have,” Hermiston said. “You can choose which screening test is best for you. While the colonoscopy is the best screening, there are options depending on your medical history, your sedation needs and personal sensitivity.”

Other Colon Screening Options

Take-home testing options are available. Talk to your provider about the availability of other cancer screening options, such as Cologuard and FIT. While many people may have worries about the colonoscopy and how it’s performed, they should know the facts:

  • Colonoscopy is low risk.
  • Patients are sedated and won’t feel any pain.
  • The test only takes about 15 minutes.

“The important thing is to have a screening of some sort at age 45,” Hermiston said. “With colorectal cancer, postponing the exam too long could be a life-threatening delay.”

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