Effect of Repeated Consumption of Partially Hydrolyzed Guar Gum on Fecal Characteristics and Gut Microbiota: A Randomized, Double-Blind, Placebo-Controlled, and Parallel-Group Clinical Trial.

Zenta Yasukawa,Makoto Ozeki,Akira Honda,Tomohisa Takagi,Ryo Inoue,Yuji Naito,Tsutomu Okubo

doi:10.3390/nu11092170

Abstract

Partially hydrolyzed guar gum (PHGG) is a water-soluble dietary fiber and is used in solid and liquid food to regulate gut function. The aim of this study was to investigate effects of PHGG on bowel movements (stool form and frequency), plasma bile acids, quality of life, and gut microbiota of healthy volunteers with a tendency toward diarrhea, i.e., irritable bowel syndrome diarrhea (IBS-D)-like symptoms. A randomized, double-blind, placebo-controlled, and parallel trial was performed on 44 healthy volunteers (22 males, 22 females, 41.9 ± 6.3 years old (average ± SD)) with minimum 7 bowel movements every week, wherein above 50% of their stool was between the Bristol stool scale (BSS) value of 5 and 6. Intake of the PHGG for 3 months significantly improved stool form, evaluated using BSS, and had no effects on stool frequency. BSS was significantly normalized in the group consuming the PHGG compared with the placebo. Comprehensive fecal microbiome analysis by the 16S rRNA-sequence method detected significant changes in the ratio of some bacteria, such as an increase of Bifidobacterium (p < 0.05) in the PHGG group. Our results suggest that intake of PHGG improves human stool form via regulating intestinal microbiota.

Highlights

The selected 44 volunteers were randomly allocated into the groups to receive Partially hydrolyzed guar gum (PHGG) or the placebo
Two additional participants used antibiotics during the stool sampling period, so these plus the previous two subjects were excluded from the fecal microbiome analysis (PHGG group, n = 2; Placebo group, n = 2)
We previously showed the proportion of the Japanese population with a Bristol stool scale (BSS) of 5–6 accounted for about one fourth to two thirds [17], so PHGG is thought to be useful for populations who tend to have diarrhea

Summary

Introduction

Increasing evidence demonstrates the bidirectional interactions within the gut-brain axis [1].Alterations in these interactions have been implicated in functional gastrointestinal disorders, such as irritable bowel syndrome (IBS) [2,3], and in psychiatric and neurologic pathologies including affective disorders [4,5], autism spectrum disorders (ASD) [4,6], Parkinson’s disease [7], multiple sclerosis [8], and chronic pain [9].Gastrointestinal symptom, including diarrhea/soft stool distress is associated with worse mental and physical health-related quality of life [10]. Increasing evidence demonstrates the bidirectional interactions within the gut-brain axis [1]. Alterations in these interactions have been implicated in functional gastrointestinal disorders, such as irritable bowel syndrome (IBS) [2,3], and in psychiatric and neurologic pathologies including affective disorders [4,5], autism spectrum disorders (ASD) [4,6], Parkinson’s disease [7], multiple sclerosis [8], and chronic pain [9]. Gastrointestinal symptom, including diarrhea/soft stool distress is associated with worse mental and physical health-related quality of life [10]. Diarrhea could be problematic in case of diseases and treatments, and in non-disease status [11,12,13,14,15,16].

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Conclusion