In the developed world, the prevalence of
diverticular disease ranges from 5% to 45%. The majority of this
population (90%) is made up of patients with distal bowel disease. Only
1.5% of cases involve solely the right side of the large bowel [1]. Prevalence by age is as follows [2]:• Age 40: 5%
• Age 60: 30%
• Age 80: 65%
Prevalence by sex:
• Age < 50: more common in males
• Age 50–70: slight preponderance in women
• Age > 70: more common in women
A low-fiber diet is considered to be the main cause of diverticular problems. First diagnosed in the United States in the early 1900s, and now common throughout developed countries, the emergence of diverticular disease coincided with the introduction of low-fiber processed foods (eg. branless refined flour). Even now, the disease is rare in Asia and Africa, where people eat high-fiber vegetable diets.
In the past, many doctors recommended that people with diverticulosis avoid seeds and nuts, including foods with small seeds, such as tomatoes and strawberries. It was thought that these tiny particles could lodge in the diverticula and cause inflammation (diverticulitis). But there is no scientific evidence that seeds and nuts cause diverticulitis. In fact, eating a high-fiber diet - which may include nuts and seeds - reduces the risk of diverticulitis. It is now believed that only foods that may irritate or get caught in the diverticula cause problems.
A low-residue Diverticulitis Diet is recommended during the flare-up periods of diverticulitis to decrease bowel volume so that the infection can heal. An intake of less than 10 grams of fiber per day is generally considered a low residue Diverticulitis Diet. If you have been on a low-residue diet for an extended period of time, your doctor may recommend a daily multi-vitamin/mineral supplement.
Once your symptoms improve, start to add about 5 to 15 grams of fiber a day to allow your digestive system to adjust to the higher fiber intake.
Although there is much conflicting information, even in the medical world, about what constitutes a good Diverticulitis Diet, the basic principle of healthy eating remains the same. Most people have no symptoms and only find out that they have Diverticulosis when they've had a colonoscopy done. If you fall into this category, the guidelines suggest that you start on a high fiber and high fluids diet as soon as possible. You should also avoid constipation at all costs.
In general, treatment depends on the severity of your signs and symptoms and whether this is your first attack of diverticulitis. If your symptoms are mild, a liquid or low-fiber diet and antibiotics may be all you need. But if you're at risk of complications or have recurrent attacks of diverticulitis, you may need more advanced care. A high-fiber diet is very important in preventing future diverticulitis attacks. As you increase your fiber intake, increase your fluid intake as well.
The diverticulitis diet has few risks. However, continuing a clear liquid diet for more than a few days can lead to weakness and other complications, since it doesn't provide enough of the nutrients your body needs. For this reason, your doctor will want you to transition back to a normal diet as soon as you can tolerate it. Your doctor may even recommend switching to a high-fiber diet to help prevent diverticulitis from recurring. Just be sure to increase the fiber in your diet slowly and aim for the level recommended by the Dietary Guidelines for Americans — at least 25 grams of fiber a day for women and 38 grams for men.
[1] Stollman NH, Raskin JB. Diverticular disease of the colon. J Clin Gastroenterol 1999;29:241–52 (PMID: 10509950).
[2] Young-Fadok TM, Roberts PL, Spencer MP, Wolff BG. Colonic diverticular disease. Curr Prob Surg 2000;37:457–514 (PMID: 10932672).
