Diverticulitis: can diet help?
In response to a public request to describe the dietary treatment prescribed for diverticulitis, I started reading the latest publications in this field and discovered that experts disagree as to what causes this condition and how it should be treated.
The traditional approaches
a) Low-residue diet
Because diverticulitis is characterised by the formation of pouch-like sections in the bowel that are prone to infection and inflammation, the original treatment approach was to advise patients to eat a low-fibre diet and to carefully avoid all foods that contained indigestible pieces, seeds or pips such as nuts, seeds, maize, popcorn, fruit peels and fruits with seeds, including figs and all berries. The theory was that such foods would enter, block and irritate the diverticulae (the little pouches) in the gut, and thus cause diverticulitis and even bowel perforation.
According to Tarleton and DiBaise (2011), no evidence has been found in the scientific literature that the low-residue (low-fibre) diet either prevents diverticulitis or assists patients suffering from this condition to improve their symptoms. These authors suggest that the time has come to discard "the myth" of the low-residue diet.
b) High-fibre diet
Another approach which has many adherents in the nutrition and medical profession is that diverticulitis is caused by a lack of fibre and other detrimental changes that have occurred in western diets combined with our modern inactive lifestyles. This theory is based on evidence that diverticulitis was very rare in those populations that used to eat a traditional diet rich in dietary fibre that contained very little meat, and still is rare in populations that continue to adhere to traditional eating patters with plenty of roughage and hardly any red meat.
Thus the recommended dietary treatment for diverticulitis was changed from avoidance of roughage to a high-fibre diet, and patients eating typical western low-fibre foods were encouraged to increase the dietary fibre and water contents of their diets.
In the past few years, researchers have also been questioning the effectiveness of the high-fibre diet in the treatment of diverticulitis. On the one hand, a comprehensive review of studies investigating the treatment and prevention of acute diverticulitis in Italy reported that the use of dietary fibre in combination with the antibiotic rifaximin (a semisynthetic, non-systemic antibiotic, which means that very little of the drug is absorbed through the walls of the gastrointestinal tract to pass into the circulation), showed a significant improvement in symptoms and a greater number of symptom-free patients after one year of the combined treatment (Maconi et al, 2011).
On the other hand, Peery and his coworkers (2012), in America, carried out a cross-sectional study of 2104 patients aged 30-80 years. The subjects underwent outpatient colonoscopy, while their diet and physical activity were evaluated. These researchers found that the experimental participants who reportedly ate the most dietary fibre, had the greatest risk of developing diverticulitis and that constipation was not a risk factor. In fact those subjects who had more than 15 bowel movements per week (i.e. about 2 motions per day), were exposed to a 70% greater risk of developing diverticulosis than subjects who had less than 7 bowel movements per week (less than 1 bowel motion per day). Surprisingly lack of physical activity and intakes of fat and red meat were not linked to the risk of developing diverticulitis.
Peery and coworkers (2012), concluded that “a high-fibre diet and increased frequency of bowel movements are associated with a greater, rather than lower, prevalence of diverticulosis". They suggest that theories relating to the causes of diverticulitis should be revised.
Strate (2012) suggests that obesity, and particularly abdominal obesity, may be linked to diverticulitis. Consequently vigorous exercise may reduce the risk of this disease as well as the bleeding induced by diverticulitis. In addition Strate (2012) recommends that alcohol should be avoided as it too has been identified as a causative factor of diverticulitis.
In 2004, Tursi proposed that when diverticulitis changes the rate of colon evacuation, this also alters the composition of the so-called microflora of the colon (i.e. the millions of bacteria that inhabit the gut exerting both beneficial and pathogenic effects), resulting in an upsurge of harmful bacteria that cause inflammation. By taking beneficial microorganisms such as probiotic supplements (e.g. Lactobacillus species or Bifidobacteria), the harmful bacteria can be prevented from taking over and initiating the vicious cycle of infection and inflammation which characterises diverticulitis. This suggestion is supported by White (2006) who confirmed that probiotics were found to have a positive effect on a variety of gastrointestinal conditions. He does, however, caution that we do not yet know what probiotics should be used to prevent or treat diverticulitis.
At the recent CNE Workshop in Johannesburg, Prof Sylvia Escott-Stump (2012) updated the audience on the potential uses of probiotics and mentioned that they may benefit inflammatory bowel diseases, which include diverticulitis. Beneficial microbes may, therefore, be a treatment of the future that will bring relief to patients suffering from diverticulitis, but it is probably premature at present to use probiotic supplements before research has identified which of these microorganisms are effective in diverticulitis.
It is apparent that the scientific community is rather baffled when it comes to making recommendations regarding the dietary treatment of diverticulitis.
In the face of the latest research findings, it is impossible to recommend that patients should eat a low-residue diet or dramatically increase their dietary fibre intake or take a specific probiotic.
Until more research has clarified the effect of diet on diverticulitis, I would like to suggest that we should all strive to eat a balanced diet, including patients with diverticulitis.
Such a balanced diet should contain adequate quantities of dietary fibre (both soluble and insoluble) obtained from plenty of wholegrain cereals, legumes, vegetables and fruit, plus moderate quantities of lean meat (2-3 servings per week), omega-3 fatty acids from fatty fish (3 servings per week), and low-fat milk or dairy products (of which at least 2 servings should be fermented - yoghurt or maas).
Drink adequate quantities of liquid (about 2,5 litres per day for adults), but don’t overdo your liquid intake and keep active. Reduce your alcohol intake and above all, do not damage the normal function of the colon by using harsh laxatives, or colon cleansing techniques. Keep in mind that too frequent bowel movements appear to be as potentially as harmful as too few when it comes to diverticulitis.
- (Dr IV van Heerden, DietDoc, July 2012)
(Photo of man with abdominal pain from Shutterstock)
( Escott-Stump S, 2012. GI Medley. Prebiotics, Probiotics & Symbiotics Lecture presented at the Sylvia Escott-Stump CNE Workshop, Sandton, 19 June 2012; Maconi G et al, 2011. Treatment of diverticular disease of the colon and the prevention of acute diverticulitis: a systematic review. Dis Colon Rectum, Vol 54(10):1326-38; Peery AF et al, 2012. A high-fibre diet does not protect against asymptomatic diverticulosis. Gastroenterology, Vol 142(2):266-72; Strate LL, 2012. Lifestyle factors and the course of diverticular disease. Digestive Diseases, Vol 30(1):35-45; Tarleton S, DiBaise JK, 2011. Low-residue diet in diverticular disease: putting an end to a myth. Nutr Clin Pract, Vol 26(2):137-42; Tursi A, 2004. Diverticular disease of the colon. The Lancet. Vol 363, Issue 9418:1397-8; White JA, 2006. Probiotics and their use in diverticulitis. Journal of Clinical Gastroenterology, Suppl. 3:S160-2)
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