Although asymptomatic diverticulosis is commonly attributed to constipation caused by a low-fiber diet, the already limited evidence of this relationship received no support from a cross-sectional, colonoscopy-based study involving 539 persons with diverticulosis and 1,569 without.1

Colonoscopy results and assessment of diet, physical activity and bowel habits revealed no association between constipation and an increased risk of diverticulosis.

In fact, participants who had less frequent bowel movements (fewer than seven per week) had reduced odds of diverticulosis compared with persons who had regular bowel movements (seven per week). Individuals who reported hard stools also had reduced odds of diverticulosis. 


Investigators also found no association between the development of diverticulosis and straining during bowel movements or having incomplete bowel movements. Finally, the researchers found no connection between dietary fiber intake and divertuculosis when comparing the highest quartile of such intake (mean 25 g/day) with the lowest (mean 8 g/day).


In a statement announcing the publication of the study, the American Gastroenterological Association asserted that diverticulosis is increasing in frequency, affecting the majority of those who reach age 80 years. In this condition, small pouches, or sacs, known as diverticula form and push outward through weak spots in the colon wall. 


Diverticular bleeding occurs when a small blood vessel within the wall of a diverticulum bursts, and diverticulitis develops when diverticula become inflamed and infected.

Another study published in the same issue determined that only about 4% of persons with diverticulosis develop acute diverticulitis, contradicting the common belief that diverticulosis has a high rate of progression.
2

References

  1. Peery AF et al. Clin Gastroenterol Hepatol. 2013;11(12):1622-1627.
  2. Shahedi K et al. Clin Gastroenterol Hepatol. 2013;11(12):1609-1613.