Flow Diagram of the study.

<p>Flow Diagram of the study.</p

Co-Administration of Soy Isoflavones and Vitamin D in Management of Irritable Bowel Disease

<div><p>Background and Aims</p><p>The substantial characteristics of Irritable Bowel Syndrome (IBS) are associated with estrogens in women. Both soy isoflavones and vitamin D can modulate estrogen receptors in the colonic smooth muscles. The aim of this study was to investigate the effects of soy isoflavones, vitamin D and their probable interactions in women with IBS.</p><p>Methods</p><p>In a factorial blinded randomized clinical trial, 100 women with IBS (age:18-75yr, were randomly assigned in 4 arms to receive either placebo of vitamin D and placebo of soy isoflavones (P+P), or placebo of vitamin D and soy isoflavones (P+S), or vitamin D and placebo of soy isoflavones (D+P), or vitamin D and soy isoflavones (D+S) for 6 weeks. Dosage of soy isoflavone was 2 capsules of 20 mg soy isoflavones per day, and dosage of vitamin D was one pearl of 50’000 IU biweekly. The clinical outcomes were IBS symptoms severity scores (IBS-SSS), disease- specific quality of life (IBS-QOL) and total score (IBS-TS) that evaluated at weeks 0, 6, and 10, and compared to each other.</p><p>Results</p><p>IBS-TS improved significantly in both S+P and D+P groups (p- value = 0.004, 0.015). The interaction effect of soy isoflavones and vitamin D on IBS-TS was significant (p<0.05). The interaction effect of soy isoflavones with vitamin D and the main effect of vitamin D on IBS-SSS were not statistically significant, whereas IBS-SSS decreased significantly in S+P and D+P groups (p-value = 0.001, 0.047 respectively).</p><p>Conclusion</p><p>Our results indicate that co-administration of soy isoflavones with vitamin D did not improve the IBS- SSS and IBS- QOL; however, it improved the IBS-TS.</p><p>Trial Registration</p><p>Clinical Trials.gov <a href="https://clinicaltrials.gov/ct2/show/NCT02026518?term=NCT02026518&rank=1" target="_blank">NCT02026518</a></p></div

The effects of soy isoflavones and/or vitamin D supplementation on abdominal distension after 6 weeks; results are adjusted for the baseline values and IBS subtype.

<p>S+P: soy isoflavones and placebo of vitamin D group, S+D: soy isoflavones and vitamin D group, P+P: placebo of soy isoflavones and placebo of vitamin D group, D+P: vitamin D and placebo of soy isoflavones group.* pso of v.</p

The effects of soy isoflavones or/ and vitamin D on the total score of IBS after 6 weeks.

<p>The effects of soy isoflavones or/ and vitamin D on the total score of IBS after 6 weeks.</p

The effects of soy isoflavones and/or vitamin D supplementation on satisfaction of bowel habits after 6 weeks; results are adjusted for the baseline values and IBS subtype.

<p>S+P: soy isoflavones and placebo of vitamin D group, S+D: soy isoflavones and vitamin D group, P+P: placebo of soy isoflavones and placebo of vitamin D group, D+P: vitamin D and placebo of soy isoflavones group.* pso of v.</p

The effects of soy isoflavones and/or vitamin D supplementation on abdominal pain duration after 6 weeks; results are adjusted for the baseline values and IBS subtype.

<p>S+P: soy isoflavones and placebo of vitamin D group, S+D: soy isoflavones and vitamin D group, P+P: placebo of soy isoflavones and placebo of vitamin D group, D+P: vitamin D and placebo of soy isoflavones group.* pso of v.</p

Estimation of effect of vitamin D on total score in Placebo and Soy isoflavones groups separately.

<p>Estimation of effect of vitamin D on total score in Placebo and Soy isoflavones groups separately.</p

Characteristics of participants in different groups at the baseline.

<p>Characteristics of participants in different groups at the baseline.</p

The effects of soy isoflavones and/or vitamin D supplementation on life disruption after 6 weeks; results are adjusted for the baseline values and IBS subtype.

<p>S+P: soy isoflavones and placebo of vitamin D group, S+D: soy isoflavones and vitamin D group, P+P: placebo of soy isoflavones and placebo of vitamin D group, D+P: vitamin D and placebo of soy isoflavones group.* pso of v</p

The effects of soy isoflavones and/or vitamin D supplementation on the IBS- SSS after 6 weeks.

<p>The effects of soy isoflavones and/or vitamin D supplementation on the IBS- SSS after 6 weeks.</p