model of a colon in the foreground with patient and doctor behind

How to Know Your Colon is Healthy

March 15, 2023

At six feet long, the colon is a large, and busy, part of your digestive system and gut. We asked Anna Krigel, MD, a gastroenterologist at Columbia University, about the colon and its health. (Spoiler: A good bowel movement is important).

How do you know if your colon is healthy?

There is no way to know for sure, but a good sign of colon health is having regular bowel movements that are easy to pass, soft but formed, and snake-like. It is not necessary to have a bowel movement every day. The quality of each bowel movement is more important than the frequency. 

What does the colon do?

The colon processes food, with the help of healthy bacteria, that was not digested by the small intestine. The colon aborbs water, minerals, and vitamins from the food. Finally, the colon forms and stores feces.

It is important to stay hydrated. Otherwise, the colon must absorb more water, leaving drier and harder stool.

How do you keep your colon healthy?

  • Drink plenty of water to keep stool hydrated. Dehydration is a major cause of constipation.
  • Consume a diet that is high in fiber. Fiber helps to retain water and stimulates the growth of healthy bacteria in the colon.
  • Consume a diet that is low in red and processed meats. Eating large amounts of red and processed meats is associated with a higher risk of colon cancer.

Should you do cleanses/detoxes to keep your colon healthy?

There is no evidence to support the use of cleanses or detoxes to keep the colon healthy.

How do you know if your colon is not healthy?

Watch out for persistently very loose or watery stools, dry or difficult-to-pass stools, or blood in the stool or with bowel movements.

When should you see a doctor if you think your colon is not healthy?

See a doctor for any new and persistent change in your bowel habits, especially if you see blood in your stool on a regular basis.

Start by discussing these changes with your primary care physician. Your doctor may refer you to a gastroenterologist (also known as a GI doctor). It is especially important to see your doctor if you have these symptoms and you are 45 years old or older and have not yet had colon cancer screening.

What tests check colon health?

There’s a variety of tests you and/or your doctor might perform to screen for colon cancer (also known as colorectal cancer). Colon cancer starts with polyps (growths) in the inner lining of the colon and can spread to other parts of the body.

The most common visual exams are colonoscopy (usually performed once every 10 years), flexible sigmoidoscopy (a less comprehensive test, usually performed once every five years), and CT colonography (the least comprehensive of these three, usually performed once every five years). In these tests, the gastroenterologist uses a camera, or CT scan, to look for growths in the colon.

Stool-based tests that you can do at home, usually once a year, are also available. The sample is sent to a lab, which looks for tiny amounts of blood or other changes associated with cancer.

It’s unlikely you will do more than one test.

Which tests are best?

Colonoscopy is the most sensitive test for the detection of early colon cancers and pre-cancerous polyps. Polyps can be removed during the test to prevent colon cancer in the future. Colonoscopy is done under sedation, for comfort, so you need a friend to escort you home afterward. Colonoscopy requires bowel preparation the day before, typically by drinking a liquid solution that cleans out the colon.

Stool-based screening can be done at home and does not require sedation or bowel preparation. Stool-based tests are very good at detecting colon cancer at an early stage but are not nearly as good at detecting the pre-cancerous polyps that can be found and removed during colonoscopy.

Unless you have an elevated risk of colon cancer due to family history of the disease or a personal history of certain diseases like inflammatory bowel disease, the decision between colonoscopy and a stool-based test is entirely up to the patient and based on the advantages and disadvantages of both.