Dietary habits and right-sided colonic diverticulosis

In Asian populations, there is a high prevalence of right-sided colonic diverticulosis, the cause of which is uncertain. It is suspected that dietary habits may interact with a congenital predilection to cause this condition. To evaluate the relationship between long-term dietary habits and the prevalence of right-sided diverticulosis in the general population, we performed a retrospective case-control study.

We reviewed the records of 3,105 screening colonoscopies performed on healthy, asymptomatic adults. All cases of right-sided diverticulosis were selected, and a similar number of gender-matched and age-matched controls with negative colonoscopies were randomly sampled from the same cohort. All case and control subjects were interviewed by a single-blinded nurse to establish their dietary habits during the past decade, in addition to other demographic characteristics. Based on consumption frequency, they were assigned to one of three diet classes for each of three food categories of interest: meat, vegetable, and fruit products. Staple foods such as rice were not included. Odds ratios were then calculated using multivariate conditional logistic regression and tests for trend were performed.

A total of 86 cases of right-sided diverticulosis were included, whereas 106 controls were randomly selected. There was a marked association between meat consumption frequency and right-sided diverticulosis, with a trend P value of <0.01 and an odds ratio of 24.81 between the most and least frequent consumers of meat products.

The prevalence of right-sided diverticulosis is strongly positively associated with past meat consumption frequency. There is no association with vegetable or fruit consumption frequency, laxative use, supplemental fiber intake, smoking, or family history.