WASHINGTON — Patients with diverticular disease can most likely eat high-fiber foods like corn, nuts, and popcorn without fear of symptom aggravation, a large prospective study suggests. In fact, some of these foods were associated with a protective effect against such symptoms.
The findings contradict the widely held assumption that foods like these, “being somewhat rougher or less well digested than other foods, would be more likely to traumatize the colon wall,” study investigator Dr. Lisa L. Strate of the division of gastroenterology at the University of Washington, Seattle, said at a press conference at the annual Digestive Disease Week.
Dr. Strate and colleagues reported findings from more than 47,000 male participants in the Health Professionals Follow-Up Study, which began in 1986. The men were aged 40–75 at baseline. The investigators analyzed data for participants who had reported newly diagnosed diverticulosis or diverticular complications at any of the intervening biennial follow-up points, through 2004.
They also examined data from a diet questionnaire sent to all participants and from a supplemental questionnaire to assess diagnosis and treatment sent to those with diverticular disease.
No multivariate associations existed between consumption of nuts, corn, popcorn, or all three and diverticular bleeding (383 incident cases) and diverticulitis (801 cases) over 18 years of follow-up after the team used a Cox proportional hazards model and controlled for dietary fiber, Dr. Strate reported at the press conference.
In addition, popcorn consumption appeared to confer a protective effect against these conditions. After adjustment for known or potential risk factors for diverticular complications, men with the highest level of popcorn consumption (at least twice a week), compared with men who ate the least popcorn (less than once per month), had a hazard ratio of 0.72 for diverticulitis, after adjustment for other potential risk factors for diverticular complications.
Similarly, for men who ate nuts at least twice per week, the diverticulitis hazard ratio was 0.8.
Physicians have historically advised patients with diverticular disease to avoid eating foods that often are incompletely digested, Dr. Strate noted at the press conference. “The recommendation stems from a theory that trauma to or obstruction of a single diverticulum results in these complications,” she said. “But, in reality, we don't understand much about the pathogenesis of these complications. At the same time, nuts and seeds were particularly thought to result in these complications, because [it was thought] they might be more likely to lodge in or to injure the mucosa.”
Over 18 years, no association existed between consumption and bleeding. ©David Allen/FOTOLIA