Dairy Consumption and Inflammatory Bowel Disease among Arab Adults: A Case-Control Study and Meta-Analysis

Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD), is a complex disease with increasing global incidence and prevalence. Although dairy consumption has been linked to various chronic diseases, its relationship with IBD remains uncertain. Additionally, there is a lack of data on this topic from Arab countries. This study aimed to investigate the association between dairy consumption and IBD through a case-control study among Arab populations, followed by a meta-analysis of available studies.

First, we used data from 158 UC patients, 244 CD patients, and 395 controls attending a polyclinic in Riyadh, Saudi Arabia. All participants were aged ≥ 18 years. Logistic regression was used to calculate the odds ratios (ORs) and 95% confidence intervals (95% CIs) of UC and CD for individuals who reported the highest versus the lowest frequencies of dairy consumption. Next, we conducted a meta-analysis, combining our results with those from other eligible studies after searching several databases. We used the I² statistics to examine statistical heterogeneity across studies and the regression test for funnel plot asymmetry to assess publication bias.

The case-control study showed a negative association between frequent dairy consumption and UC (OR (95% CI) = 0.64 (0.41, 1.00)) but not CD (OR (95% CI) = 0.97 (0.65, 1.45)). In the meta-analysis, the highest frequencies of dairy consumption were negatively associated with both UC and CD: ORs (95% CIs) = 0.82 (0.68, 0.98) and 0.72 (0.59, 0.87), respectively. A moderate heterogeneity across studies was noticed in the UC meta-analysis (I² = 59.58%) and the CD meta-analysis (I² = 41.16%). No publication bias was detected.

Frequent dairy consumption could protect against the development of UC and CD, suggesting potential dietary recommendations in the context of IBD prevention.