The efficacy of vitamin D supplementation for irritable bowel syndrome: a systematic review with meta-analysis

Abstract

Background Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder involving gut-brain interactions with limited effective treatment options. Vitamin D deficiency is commonly observed in patients with IBS, but whether vitamin D supplementation ameliorates IBS is controversial in randomized controlled trials. The present systematic review and meta-analysis explored the efficacy of vitamin D supplementation in patients with IBS. Methods We performed a systematic search of potentially relevant publications from PubMed, EMBASE, the Cochrane Central Register of Controlled Studies and the Web of Science up until January 2022. We assessed the weighted mean difference (WMD) and 95% confidence interval (95% CI) of the IBS severity scoring system (IBS-SSS), IBS quality of life (IBS-QoL) and IBS total score (IBS-TS) before and after vitamin D supplementation intervention. Results We included four randomized, placebo-controlled trials involving 335 participants. The differences in IBS-SSS score between participants in the intervention group and the placebo group increased after intervention (WMD: -55.55, 95% CI: -70.22 to -40.87, I2 = 53.7%, after intervention; WMD: -3.17, 95% CI: -18.15 to 11.81, I2 = 0.0%, before intervention). Participants receiving vitamin D supplementation showed greater improvement in IBS-SSS after intervention than participants receiving placebo treatment (WMD: -84.21, 95% CI: -111.38 to -57.05, I2 = 73.2%; WMD: -28.29, 95% CI: -49.95 to -6.62, I2 = 46.6%, respectively). Vitamin D supplementation was also superior to placebo in IBS-QoL improvement (WMD: 14.98, 95% CI: 12.06 to 17.90, I2 = 0.0%; WMD: 6.55, 95% CI: -2.23 to 15.33, I2 = 82.7%, respectively). Sensitivity analyses revealed an unstable pooled effect on IBS-TS in participants receiving vitamin D supplementation. Therefore, we did not evaluate the efficacy of vitamin D intervention in IBS-TS. Conclusions This systematic review and meta-analysis suggested that vitamin D supplementation was superior to placebo for IBS treatment.

The Effect of Vitamin D Supplementation on the Severity of Symptoms and the Quality of Life in Irritable Bowel Syndrome Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

“…We clarified the methodological flaws of Chong et al [55] in our recently published editorial [59]. In another recent review by Haung et al [60], vitamin D was effective in improving IBS-SSS which is also contradictory to our findings. This difference is attributed to the narrow and defective searching technique excluding three includable studies [29,31,32] especially Williams et al [31] and Jalili et al, 2019 [29] which showed no effect of vitamin D on IBS-SSS.…”

The Role of Calcium, 25-Hydroxyvitamin D and Parathyroid Hormone in Irritable Bowel Syndrome: A Bidirectional Two-Sample Mendelian Randomization Study

“…Jalili et al conducted a randomized, double-blind, placebo-controlled clinical trial to assess the impact of Vit-D supplementation on symptoms severity and quality of life (QOL) in IBS patients and found that compared to the placebo group, Vit-D therapy could markedly improve the symptoms and QOL of IBS patients [9]. Similarly, a systematic review and meta-analysis including 4 randomized, placebo-controlled trials showed that Vit-D supplementation was remarkably superior to placebo in improving the symptom severity (WMD: -84.21, 95% CI: -111.38 to -57.05, I 2 = 73.2%; WMD: -28.29, 95% CI: -49.95 to -6.62, I 2 = 46.6%, respectively) and QOL (WMD: 14.98, 95% CI: 12.06 to 17.90, I 2 = 0.0%; WMD: 6.55, 95% CI: -2.23 to 15.33, I 2 = 82.7%, respectively) of IBS patients [25]. However, the other randomized, double-blind, placebocontrolled study by Williams et al demonstrated that there were no improvements in the IBS symptom severity and QOL between the trial (Vit-D supplementation) and placebo groups [10].…”

The Role of Calcium, 25-Hydroxyvitamin D, and Parathyroid Hormone in Irritable Bowel Syndrome: A Bidirectional Two-Sample Mendelian Randomization Study

“…Jalili et al conducted a randomized, double-blind, placebo-controlled clinical trial to assess the impact of Vit-D supplementation on symptoms severity and quality of life (QOL) in IBS patients and found that, compared to the placebo group, Vit-D therapy could markedly improve the symptoms and QOL of IBS patients [ 14 ]. Similarly, a systematic review and meta-analysis including four randomized, placebo-controlled trials showed that Vit-D supplementation was remarkably superior to placebo in improving the symptom severity (WMD: −84.21, 95% CI: −111.38 to −57.05, I 2 = 73.2%; WMD: −28.29, 95% CI: −49.95 to −6.62, I 2 = 46.6%, respectively) and QOL (WMD: 14.98, 95% CI: 12.06 to 17.90, I 2 = 0.0%; WMD: 6.55, 95% CI: −2.23 to 15.33, I 2 = 82.7%, respectively) of IBS patients [ 30 ]. However, the other randomized, double-blind, placebo-controlled study by Williams et al demonstrated that there were no improvements in the IBS symptom severity and QOL between the trial (Vit-D supplementation) and placebo groups [ 15 ].…”