What causes diverticulitis?


Diverticulitis is caused by little sacs, or diverticula, in the intestine that are very swollen or infected, causing abdominal pain. The causes of diverticulitis are still being determined.These small sacs are rarely found in the digestive tract of patients under 40, but become more common as patients age. By age 90, almost everyone has diverticula. These may become infected by trapped objects or feces. Diverticulitis is also more common in patients who are taking drugs that suppress their immune system, because they are at risk for infection. It is believed that people who eat low-fiber diets, do not exercise, and are obese are at higher risk for diverticula, and thus diverticulitis.

Picture of obstructed diverticula
Dr. Michael Roizen, MD
Internal Medicine
You have three layers in the walls of your intestines. Where there's a little break between muscles, feces can squeeze into the gap and become as hard as clay. When that happens, the small out-pouches (they look a little like small thumbs poking out of the side of the colon) can get inflamed and cause diverticulitis. It usually occurs when the colon wall has to squeeze too hard to move the caca along-which is an indication of too little fiber in the diet.

There's a myth that says nuts can get stuck in little pouches in your colon and cause diverticulitis, but they're innocent. In fact, there's never been a case where nuts have been implicated as the perpetrator. The real culprit is not having enough fiber and water in your diet.
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YOU: The Owner's Manual, Updated and Expanded Edition: An Insider's Guide to the Body that Will Make You Healthier and Younger

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Diverticulitis occurs when diverticula (small, bulging pouches in the digestive tract) become infected or inflamed. Some signs of diverticulitis include severe pain, bloating that persists for weeks, constipation and blood in your ...

stool. Treatment includes changes in diet, antibiotics and surgery.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.