Vegetarian Diet May Protect Against Diverticular Disease
A new study finds vegetarians are a third less likely to than meat eaters to develop diverticular disease. The study was published online yesterday in the British Medical Journal.
Diverticular disease has been termed a “disease of western civilization” because of the higher numbers of cases in countries like the UK and the US compared with parts of Africa. The condition affects the large bowel or colon and is thought to be caused by not consuming enough fiber.
People with diverticular disease have small pouches in the lining of the colon that bulge outward through weak spots or pouches called a diverticula. The condition of having diverticula is called diverticulosis. In the United States, approximately 10% of adults older than 40 have diverticulosis and about half of all adults older than 60.
When the pouches become inflamed, the condition is called diverticulitis. Ten to 25% of people with diverticulosis get diverticulitis. The two conditions, diverticulosis and diverticulitis, make up diverticular disease.
Most people with diverticulosis do not have any discomfort or symptoms. Others experience painful abdominal cramps, bloating, wind, constipation and diarrhea.
The most common symptom of diverticulitis is abdominal pain. The person may also experience cramping, nausea, vomiting, fever, chills, or a change in bowel habits.
Previous research has suggested that a low fiber diet could lead to diverticular disease, and that vegetarians may have a lower risk compared with meat eaters, but there is little evidence to substantiate this.
To examine the link between a vegetarian diet and intake of dietary fiber with the risk of diverticular disease, Dr Francesca Crowe, Cancer Epidemiology Unit at the University of Oxford, and colleagues, analyzed data from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Oxford study.
The EPIC-Oxford study with a cohort of 47,033 mainly health conscious participants recruited from around the United Kingdom. Of those, 15,459 (33%) reported consuming a vegetarian diet.
After an average follow-up time of 11.6 years, there were 812 cases of diverticular disease (806 admissions to hospital and six deaths). After adjusting the factors such as smoking, alcohol and body mass index (BMI), vegetarians had a 31% lower risk (relative risk 0.69, 95% confidence interval 0.55 to 0.86) of diverticular disease compared with meat eaters.
Furthermore, participants with a relatively high intake of dietary fiber (around 25g a day) had a lower risk of being admitted to hospital with or dying from diverticular disease compared with those who consumed less than 14g of fiber a day (3.0% vs 4.4% respectively).
Consuming a vegetarian diet and a high intake of dietary fiber are both associated with a lower risk of diverticular disease, say the authors. Participants in the highest fifth for fiber intake (≥25.5 g/day for women and ≥26.1 g/day for men) had a 41% lower risk (0.59, 0.46 to 0.78; P
The 2000-1 UK National Diet and Nutrition Survey showed that 72% of men and 87% of women were not meeting the recommended average intake for dietary fiber of 18 g per day and so the proportion of cases of diverticular diseases in the general population attributed to a low fiber diet could be considerable, they add.
These findings lend support to the public health recommendations that encourage the consumption of foods high in fiber such as whole meal breads, wholegrain cereals, fruits and vegetables, they conclude.
In an accompanying editorial, researchers from Nottingham University Hospital discuss the implications for the health of the population and the individual.
Based on these findings, David Humes and Joe West estimate that “about 71 meat eaters would have to become vegetarians to prevent one diagnosis of diverticular disease.”
They add: “Overall the opportunity for preventing the occurrence of diverticular disease and other conditions, such as colorectal cancer, probably lies in the modification of diet, at either a population or an individual level.” However, they stress that “far more evidence is needed before dietary recommendations can be made to the general public.”
The above story is reprinted (with editorial adaptations by Ramona Bates, MD) from materials provided by BMJ-British Medical Journal.
Francesca L Crowe, Paul N Appleby, Naomi E Allen and Timothy J Key. Diet and risk of diverticular disease in Oxford cohort of European Prospective Investigation into Cancer and Nutrition (EPIC): prospective study of British vegetarians and non-vegetarians. BMJ, 2011; 343:d4131 DOI: 10.1136/bmj.d4131
David J Humes and Joe West. Diet and risk of diverticular disease. BMJ, 2011; 343:d4115 DOI: 10.1136/bmj.d4115