Effects of Ellagic Acid on Oxidative Stress Index, Inflammatory Markers and Quality of Life in Patients With Irritable Bowel Syndrome: Randomized Double-blind Clinical Trial

Irritable bowel syndrome (IBS) is a common disorder that affects the large intestine. Oxidative stress and inflammation play a major role in IBS. Considering the antioxidant properties of ellagic acid (EA), this study was designed to evaluate the effect of EA on oxidative stress index, inflammatory markers, and quality of life in patients with IBS. This research was conducted as a randomized, double-blind, placebo-controlled clinical trial; 44 patients with IBS were recruited. Patients who met the inclusion criteria were randomly allocated to consume a capsule containing 180 mg of EA per day (n = 22) or a placebo (n = 22) for 8 weeks. Serum levels of total antioxidant capacity (TAC), malondialdehyde (MDA), C-reactive protein (CRP), and interleukin-6 (IL-6) were measured at the beginning and the end of the study. Also, quality of life was assessed using a self-report questionnaire for IBS patients (IBS-QOL). At the end of the study, we saw a significant decrease and increase in the MDA and TAC in the intervention group, respectively (p < 0.05). Also, EA consumption reduced CRP and IL-6 levels, and these changes were significant in comparison with placebo group changes (p < 0.05). The overall score of IBS-QOL significantly decreased, and quality of life was increased (p < 0.05), but there were no significant changes in the placebo group. According to these findings, receiving polyphenols, such as EA, may help maintain intestinal health by modulating inflammation and oxidative stress and ultimately improving the quality of life in IBS patients. Trial Registration Iranian Registry of Clinical Trials Identifier: IRCT20141025019669N11