Dr. Rachel: How often do you need a colonoscopy?

NEW ORLEANS -- Our teaching doctor, Dr. Rachel Reitan, got an excellent email from a viewer recently about colonoscopies.

Here's what the email asked:

"I’m 50 years old and had my first colonoscopy. My doctor said it was normal and that I needed to return in 10 years. My friend had one as well and she needs to return in three years. Why does she need one so much sooner?"

Here's what Dr. Rachel has to say:

"It’s recommended that people get screened at age 50, unless there’s a family history of colorectal cancer. If that’s the case, you need to get the screening 10 years before the age the person was who was diagnosed with cancer.

Colorectal cancer is the third leading cause of cancer-related deaths in the U.S. That’s unfortunate because it is a preventable cancer. Most cancer starts as a polyp or growth in the colon or rectum. These polyps can change into cancer over years. When you have a colonoscopy, the polyps are removed.

If your colonoscopy is normal, then doctors usually recommend one every 10 years. If polyps are removed, you’ll have to get them sooner."