---
title: The Latest on Saccharomyces boulardii and GI Health
description: In animal studies, the probiotic yeast Saccharomyces boulardii improved transit time by 30% and supported anxiety-like behavior in a model of IBS.
---

[Evidence-based Wellness Education](https://www.casi.org/articles)

# [The Latest on Saccharomyces boulardii and GI Health](https://www.casi.org/articles/the-latest-on-saccharomyces-boulardii-and-gi-health)

 Written by [Cory Ambrose, ND, MAT](https://www.casi.org/articles/author/cory-ambrose-nd-mat) | Feb 15, 2022, 12:00:00 PM

The gastrointestinal (GI) microbiome consists of many types of health-supportive agents, including bacteria, fungi, archaea, and viruses. *Saccharomyces boulardii* (*S. boulardii*) is a probiotic species of yeast being studied for its support of GI health. Its cell walls contain beta-glucans, chitin, and mannoproteins that aid in the fermentation process and production of short-chain fatty acids, such as butyrate. In recent studies, [S. boulardii has been shown to support GI function](https://pubmed.ncbi.nlm.nih.gov/33811908/) in the presence of bacterial diarrhea, antibiotic-associated diarrhea, gut dysbiosis, and other GI disorders, such as irritable bowel syndrome (IBS).

IBS involves intestinal dysfunction, inflammation, and changes to the gut microbiome. It may also influence the [gut-brain connectio](https://pubmed.ncbi.nlm.nih.gov/32955166/)n and psychosocial status. Conditions such as depression and anxiety are often associated with IBS.

A controlled animal study published by [Constante and colleagues](https://pubmed.ncbi.nlm.nih.gov/32955166/) explored the efficacy of supplementation with *S. boulardii* on mice colonized with microbes from individuals with IBS and comorbid anxiety. The study subjects were fed *S. boulardii* for 2 weeks. The biomarkers and behaviors assessed were related to intestinal permeability, anxiety-like behavior, and transit time.

The [study results](https://pubmed.ncbi.nlm.nih.gov/32955166/) showed a 30% improvement in transit time in the presence of S. boulardii in mice colonized with microbes related to IBS and comorbid anxiety. Improvements in anxiety-like behaviors were also observed. [Taxonomic differences](https://pubmed.ncbi.nlm.nih.gov/32955166/) in gut microbiota were observed in the S. boulardii group.

In [another study](https://pubmed.ncbi.nlm.nih.gov/33811908/) model, the impact of supplementation with *S. boulardii* in the presence of antibiotic-associated gut dysbiosis was tested. Antibiotics were administered to a murine population for 14 days to induce gut dysbiosis. After that period, *S. boulardii* was administered to the treatment group for 21 days. A second round of antibiotics was administered concurrently.

After the initial administration of antibiotics, [the authors observed](https://pubmed.ncbi.nlm.nih.gov/33811908/) a decrease in probiotic genera including *Lactobacillus*, *Bifidobacterium*, *Clostridium*, and *Firmicutes*. Biomarkers related to oxidative stress, including glutathione and superoxide dismutase (SOD) were also shown to decrease during the antibiotic period. After receiving *S. boulardii*, the study subjects experienced a restoration of probiotic populations and levels of [glutathione](https://pubmed.ncbi.nlm.nih.gov/33811908/) and SOD. Improvements in villus height, crypt depth, and levels of certain inflammatory markers, including myeloperoxidase were also observed. Certain parameters related to the [gut-brain axis](https://pubmed.ncbi.nlm.nih.gov/33811908/) were measured and found to be influenced by the administration of *S. boulardii*.

*S. boulardii* is a probiotic species of yeast with the potential to support many aspects of GI health. It also may support the body’s response to oxidative stress and inflammation, the gut-brain connection, and a healthy gut microbiome.

[View full post](https://www.casi.org/articles/the-latest-on-saccharomyces-boulardii-and-gi-health)

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