Effects of 14-weeks betaine supplementation on pro-inflammatory cytokines and hematology status in professional youth soccer players during a competition season: a double blind, randomized, placebo-controlled trial

Abstract

Objective

Systemic elevations in pro-inflammatory cytokines are a marker of non-functional over reaching, and betaine has been shown to reduce the secretion of pro-inflammatory cytokines in vitro. The aim of this study was to investigate the effects of betaine supplementation on tumor necrosis factor alpha (TNF-α), interleukins-1 beta (IL-1β), − 6 (IL-6) and the complete blood cell (CBC) count in professional youth soccer players during a competitive season.

Methods

Twenty-nine soccer players (age, 15.5 ± 0.3 years) were randomly divided into two groups based on playing position: betaine group (BG, n = 14, 2 g/day) or placebo group (PG, n = 15). During the 14-week period, training load was matched and well-being indicators were monitored daily. The aforementioned cytokines and CBC were assessed at pre- (P1), mid- (P2), and post- (P3) season.

Results

Significant (p < 0.05) group x time interactions were found for TNF-α, IL-1β, and IL-6. These variables were lower in the BG at P2 and P3 compared to P1, while IL-1β was greater in the PG at P3 compared to P1 (p = 0.033). The CBC count analysis showed there was significant group by time interactions for white blood cells (WBC), red blood cells (RBC), hemoglobin (Hb), and mean corpuscular hemoglobin concentration (MCHC). WBC demonstrated increases at P3 compared to P2 in PG (p = 0.034); RBC was less at P3 compared to P1 in BG (p = 0.020); Hb was greater at P2 compared to P1, whilst it was less at P3 compared to P3 for both groups. MCHC was greater at P3 and P2 compared to P1 in BG, whereas MCHC was significantly lower at P3 compared to P2 in the PG (p = 0.003).

Conclusion

The results confirmed that 14 weeks of betaine supplementation prevented an increase in pro-inflammatory cytokines and WBC counts. It seems that betaine supplementation may be a useful nutritional strategy to regulate the immune response during a fatiguing soccer season.

Keywords:

• Nonfunctional over-reaching
• Youth sports
• Immune system
• Football
• IL-1β

Acknowledgments

The authors would like to thank the players who participated in this study, Deputy Vice-Chancellor for Research and Technology, University of Isfahan and the Sepahan Professional Club. We also thank Dr. Jenna Bartley for her valuable guidance.

Authors’ contributions

Conceptualization, HN, JPG, and JMC, methodology, HN, JMC, and JPG, data collection, HN, analysis, HN and JMC, writing—original draft preparation, HN, and ACR, writing—review and editing, HN, JMC, ACR, and JPG. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Availability of data and materials

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Declarations

Ethics approval and consent to participate

Players, as well as their parents, signed a consent letter to participate in the project. Prior to the start of the study, the Ethics Committee of the University of Isfahan approved the study (IR.UI.REC.1398.102), and the recommendations of Human Ethics in Research were followed by the Helsinki Declaration.

Consent for publication

No individual or indemnifiable data is being published as part of this manuscript.

Competing interests

The authors declare that they have no competing interests.

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