Inflammatory bowel disease (IBD) is a group of immune-mediated chronic disorders that are divided into two major types of ulcerative colitis (UC) and Crohn's disease (CD). Dietary supplementation has beneficial effects in management of ulcerative colitis. In this study, we aimed to investigate the association between dietary supplementation and inflammatory markers in patients with ulcerative colitis.

This cross-sectional study was conducted on patients with ulcerative colitis at the Alimentary Tract Research Center. A questionnaire about demographic and dietary supplementation data was filled for each patient. Blood samples were taken after overnight fasting for measuring ESR, hs-CRP, and TNF-α. Data were analyzed using SPSS version 17.0.

Sixty patients were eligible for the study and completed it. Thirty-nine participants were female (65 %). The mean age of participants was 36.4 ± 10.3. Forty patients used dietary supplements including Calcium (25%), Vitamin D (48.3%), Folic acid (11.6%), Iron (18.3%), Multivitamin (0.5%) and twenty patients (33.3%) didn’t use any supplements. Level of hs-CRP was significantly lower in patients that used vitamin D (P-value=0.003) and iron supplement (P-value=0.001).

The results of the study showed that dietary vitamin D and iron supplementation have related to lower hs-CRP levels in patients with ulcerative colitis.