Effects of probiotic supplementation on respiratory infection and immune function in athletes: systematic review and meta-analysis of randomized controlled trials.
Karolina Łagowska, Joanna Bajerska
Objective: The aim of this study was to evaluate the effectiveness of probiotic supplementation on upper tract respiratory infection and inflammatory markers in elite athletes.
Data sources: We identified sources by searching the PubMed, EBSCO host, Scopus, and Web of Science databases using the following search terms: “probiotic” OR “probiotics” AND “exercise” OR “sport” OR “athletes” AND “URTI” OR “respiratory infection” OR “upper respiratory tract infections” OR “inflammation” OR “inflammatory OR “cytokines”.
Study selection: We screened the title and abstracts of 2498 articles using our inclusion critieria. A total of 14 articles were selected for further analysis.
Data Extraction: Data from the included studies were extracted by 2 independent reviewers. These data included the study design, participant characteristics, inclusion and exclusion, intervention characteristics, outcome measures, and the main results of the study.
Data Synthesis: The meta-analysis did not show any significant effect of probiotic supplementation on the number of days of illness or the mean number and duration of URTI episodes, but there was a significant effect of probiotic supplementation on total symptom severity score (–0.65, 95% CI: –1.05; –0.25, p = 0.02). Lower levels of IL-6 (–2.52 pg/ml, 95% CI: –4.12, –0.51, p = 0.001) and TNF-α (–2.31 pg/ml, 95% CI: –4.12, –0.51, p = 0.008) were also reported after supplementation.
Conclusions: This meta-analysis provides evidence that probiotic supplementation, especially among professional athletes, is an effective way to decrease the total URTI symptom severity score. Additionally, probiotic supplementation may decrease TNF-α and IL-6 levels. There is a need for more studies with larger groups to better estimate this effect. It is necessary to determine the best timing, duration, composition and dose of such supplementation.
Key words: upper respiratory tract infection, athletes, probiotic, inflammatory
Athl Train. 2021 Jan 22. doi: 10.4085/592-20. Epub ahead of print. PMID: 33481001.
https://meridian.allenpress.com/jat/article-lookup/doi/10.4085/592-20
