Effect of prebiotics, probiotics, and synbiotics on gastrointestinal outcomes in healthy adults and active adults at rest and in response to exercise-A systematic literature review.
- 2022-12-07
- Frontiers in nutrition 9
- Christopher E Rauch
- Alice S Mika
- Alan J McCubbin
- Zoya Huschtscha
- Ricardo J S Costa
- PubMed: 36570133
- DOI: 10.3389/fnut.2022.1003620
Introduction
A systematic literature search was undertaken to assess the impact of pre-, pro-, and syn-biotic supplementation on measures of gastrointestinal status at rest and in response to acute exercise.Methods
Six databases (Ovid MEDLINE, EMBASE, Cinahl, SportsDISCUS, Web of Science, and Scopus) were used. Included were human research studies in healthy sedentary adults, and healthy active adults, involving supplementation and control or placebo groups. Sedentary individuals with non-communicable disease risk or established gastrointestinal inflammatory or functional diseases/disorders were excluded.Results
A total of n = 1,204 participants were included from n = 37 papers reported resting outcomes, and n = 13 reported exercise-induced gastrointestinal syndrome (EIGS) outcomes. No supplement improved gastrointestinal permeability or gastrointestinal symptoms (GIS), and systemic endotoxemia at rest. Only modest positive changes in inflammatory cytokine profiles were observed in n = 3/15 studies at rest. Prebiotic studies (n = 4/5) reported significantly increased resting fecal Bifidobacteria, but no consistent differences in other microbes. Probiotic studies (n = 4/9) increased the supplemented bacterial species-strain. Only arabinoxylan oligosaccharide supplementation increased total fecal short chain fatty acid (SCFA) and butyrate concentrations. In response to exercise, probiotics did not substantially influence epithelial injury and permeability, systemic endotoxin profile, or GIS. Two studies reported reduced systemic inflammatory cytokine responses to exercise. Probiotic supplementation did not substantially influence GIS during exercise.Discussion
Synbiotic outcomes resembled probiotics, likely due to the minimal dose of prebiotic included. Methodological issues and high risk of bias were identified in several studies, using the Cochrane Risk of Bias Assessment Tool. A major limitation in the majority of included studies was the lack of a comprehensive approach of well-validated biomarkers specific to gastrointestinal outcomes and many included studies featured small sample sizes. Prebiotic supplementation can influence gut microbial composition and SCFA concentration; whereas probiotics increase the supplemented species-strain, with minimal effect on SCFA, and no effect on any other gastrointestinal status marker at rest. Probiotic and synbiotic supplementation does not substantially reduce epithelial injury and permeability, systemic endotoxin and inflammatory cytokine profiles, or GIS in response to acute exercise.Research Insights
| Supplement | Health Outcome | Effect Type | Effect Size |
|---|---|---|---|
| Lactobacillus rhamnosus lysate powder | Altered Gut Microbial Community Composition | Beneficial | Small |
| Lactobacillus rhamnosus lysate powder | Altered Pro-Inflammatory Cytokine Levels | Beneficial | Small |
| Lactobacillus rhamnosus lysate powder | Exercise-Induced Gastrointestinal Symptoms | Neutral | Small |
| Lactobacillus rhamnosus lysate powder | Reduced Gastrointestinal Symptoms | Neutral | Small |
| Lactobacillus rhamnosus lysate powder | Reduced Intestinal Permeability | Neutral | Small |
| Lactobacillus rhamnosus lysate powder | Reduced Metabolic Endotoxemia | Neutral | Small |
| Lactobacillus rhamnosus lysate powder | Reduced Systemic Endotoxemia at Rest | Neutral | Small |
| Lactobacillus salivarius UCC118 | Increased Abundance of Specific Bacterial Species | Beneficial | Small |
| Lactobacillus salivarius UCC118 | Increased Fecal Probiotic Strains | Beneficial | Small |
| Lactobacillus salivarius UCC118 | Increased Gut Microbial Supplementation | Beneficial | Small |
| Lactobacillus salivarius UCC118 | No Improvement in Gastrointestinal Permeability | Neutral | Small |
| Lactobacillus salivarius UCC118 | No Substantial Reduction in Exercise-Induced Gastrointestinal Injury, Permeability, Endotoxin Response, or Gastrointestinal Symptoms | Neutral | Small |
| Lactobacillus salivarius UCC118 | Unchanged Gastrointestinal Symptoms | Neutral | Small |