Many people have small pouches in the lining of the colon, large intestine, that bulge outward through weak spots. Each pouch is called a diverticulum. The condition of having multiple pouches is called diverticulosis. About 10 percent of Americans older than 40 have diverticulosis.1 The condition becomes more common as people age. About half of all people older than 60 have diverticulosis.2
Diverticula are most common in the lower portion of the large intestine, called the sigmoid colon. When the pouches become inflamed, the condition is called diverticulitis. Ten to 25 percent of people with diverticulosis get diverticulitis.3 Diverticulosis and diverticulitis together are called diverticular disease.
Most people with diverticulosis do not have any discomfort or symptoms. However, some people may experience crampy pain or discomfort in the lower abdomen, bloating, and constipation. Other conditions such as irritable bowel syndrome and stomach ulcers cause similar problems, so the symptoms do not always mean a person has diverticulosis. People with chronic symptoms should visit their doctor or health care provider.
The most common symptom of diverticulitis is abdominal pain. The most common sign on examination is tenderness in the lower left side of the abdomen. Usually, the pain is severe and comes on suddenly, but it can also be mild and become worse over several days. The intensity of the pain can fluctuate. A person may experience cramping, nausea, vomiting, fever, chills, or a change in bowel habits.
Increasing the amount of fiber in the diet may reduce symptoms of diverticulosis and prevent complications such as diverticulitis. Fiber keeps stool soft and lowers pressure inside the colon so that bowel contents can move through easily. The American Dietetic Association recommends consuming 20 to 35 grams of fiber each day. See the handout for high fiber diet.
Avoidance of nuts, popcorn, and sunflower, pumpkin, caraway, and sesame seeds has been recommended by physicians out of fear that food particles could enter, block, or irritate the diverticula. However, no scientific data support this treatment measure. Eating a high-fiber diet is the only requirement highly emphasized across the medical literature. Eliminating specific foods is not necessary. The seeds in tomatoes, zucchini, cucumbers, strawberries, and raspberries, as well as poppy seeds, are generally considered harmless. People differ in the amounts and types of foods they can eat. Decisions about diet should be made based on what works best for each person. Keeping a food diary may help identify what foods may cause symptoms.
Treatment for diverticulitis focuses on clearing up the inflammation and infection, resting the colon, and preventing or minimizing complications.
Depending on the severity of symptoms, the doctor may recommend bed rest, oral antibiotics, a pain reliever, and a liquid diet. If symptoms ease after a few days, the doctor will recommend gradually increasing the amount of high-fiber foods in the diet.
Severe cases of diverticulitis with acute pain and complications will likely require a hospital stay. Most cases of severe diverticulitis are treated with IV antibiotics and a few days without food or drink to help the colon rest. In some cases, surgery may be necessary.
NIH Publication No. 08–1163