Medical researchers might need to go back to the drawing board to figure out the causes of diverticulosis, the small pouches that commonly form along the colon wall and are sometimes associated with a painful condition called diverticulitis.
Conventional wisdom has held that low-fiber diets contribute to diverticulosis. That’s partly because the condition began being diagnosed more frequently as American diets began to rely more heavily on processed foods and less on fresh fruits and vegetables. Regions of the world with high-fiber diets seem to have less diverticular disease.
Now medical experts are not so sure about blaming low-fiber diets. A study out of the University of North Carolina concludes that it’s actually high-fiber diets that might contribute to diverticulosis.
The UNC School of Medicine in Chapel Hill gathered data on more than 2,000 people ages 30 to 80 who had undergone an outpatient colonoscopy at UNC Hospitals from 1998 to 2010. Participants were interviewed about their diet, bowel movements and level of physical activity.
- A low-fiber diet was not associated with a higher prevalence of asymptomatic diverticulosis.
- Those participants with the lowest fiber intake were 30 percent less likely to develop pouches along the colon than those with the highest fiber intake.
- Those with more than 15 bowel movements per week were 70 percent more likely to develop diverticulosis than those having fewer than seven bowel movements per week.
- No link could be found between diverticulosis and physical inactivity, intake of fat or intake of red meat.
“Despite the significant morbidity and mortality of symptomatic diverticulosis, it looks like we may have been wrong, for decades, about why diverticula actually form,” said Dr. Anne Peery, the study’s lead researcher, a fellow in gastroenterology and hepatology at UNC.
The study appears in the February 2012 issue of the journal Gastroenterology.
“While it is too early to tell patients what to do differently, these results are exciting for researchers,” said Peery in a UNC media release.