Diverticulosis occurs when small, bulging sacs or pouches form on the inner wall of the intestine. These sacs are called diverticula. Most often, these pouches form in the large intestine (colon). They may also occur in the in the jejunum in the small intestine, although this is less common.
Diverticulosis is less common in people age 40 and younger. It's more common in older adults. About half of Americans over age 60 have this condition. Most people will have it by age 80.
No one knows exactly what causes these pouches to form.
For many years, it was thought that eating a low-fiber diet may play a role. Not eating enough fiber can cause constipation (hard stools). Straining to pass stools (feces) increases the pressure in the colon or intestines. This may cause the pouches to form at weak spots in the colon wall. However, whether a low-fiber diet leads to this problem is not well proven.
Other possible risk factors that are also not well proven are lack of exercise and obesity.
Eating nuts, popcorn, or corn does not appear to lead to inflammation of these pouches (diverticulitis).
Most people with diverticulosis have no symptoms.
When symptoms occur, they may include:
You may notice small amounts of blood in your stools or on toilet paper. Rarely, more severe bleeding may occur.
Diverticulosis is often found during an exam for another health problem. For example, it is often discovered during a colonoscopy.
If you do have symptoms, you may have one or more of the following tests:
A colonoscopy is needed to make the diagnosis:
Because most people have no symptoms, most of the time, no treatment is needed.
Your health care provider may recommend getting more fiber in your diet. A high-fiber diet has many health benefits. Most people don't get enough fiber. To help prevent constipation, you should:
You should avoid NSAIDs such as aspirin, ibuprofen (Motrin), and naproxen (Aleve). These medicines can make bleeding more likely.
For bleeding that does not stop or recurs:
If bleeding does not stop or recurs many times, removal of a section of the colon may be needed.
Most people who have diverticulosis have no symptoms. Once these pouches have formed, you will have them for life.
Up to 25% of people with the condition will develop diverticulitis. This occurs when small pieces of stool become trapped in the pouches, causing infection or swelling.
More serious problems that may develop include:
Call your provider if symptoms of diverticulitis occur.
Reviewed By: Michael M. Phillips, MD, Clinical Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.