Background & Aims
Asymptomatic diverticulosis is commonly attributed to constipation secondary to a low-fiber diet, although evidence for this mechanism is limited. We examined the associations between constipation and low dietary fiber intake with risk of asymptomatic diverticulosis.
Methods
We performed a cross sectional study, analyzing data from 539 individuals with diverticulosis and 1569 without (controls). Participants underwent colonoscopy and assessment of diet, physical activity and bowel habits. Our analysis was limited our analysis to participants with no knowledge of their diverticular disease, to reduce the risk of biased responses.
Results
Constipation was not associated with an increased risk of diverticulosis. Participants with less frequent bowel movements (BM: <7/wk) had reduced odds of diverticulosis compared to those with regular (7/wk) BM (odds ratio [OR] 0.56, 95% confidence interval [CI], 0.40–0.80). Those reporting hard stools also had a reduced odds (OR, 0.75; 95% CI, 0.55–1.02). There was no association between diverticulosis and straining (OR, 0.85; 95% CI, 0.59–1.22) or incomplete BM (OR, 0.85; 95% CI, 0.61–1.20). We found no association between dietary fiber intake and diverticulosis (OR, 0.96; 95% CI, 0.71–1.30) in comparing the highest quartile to the lowest (mean intake 25 versus 8 g/day).
Conclusions
In our cross-sectional, colonoscopy-based study, neither constipation nor a low-fiber diet was associated with an increased risk of diverticulosis.