Prevalence and adverse effects of sport-related nutritional supplements (sport drinks, bars, and gels) in the military before and during the COVID-19 pandemic: the US Military Dietary Supplement Use Study

ABSTRACT

Background

Sport-related nutritional supplements (SRNS) include sport drinks, sport bars, and sport gels. This investigation examined temporal patterns in SRNS use and adverse effects (AEs) reported by a single cohort of United States active-duty service members (SMs) surveyed before and during the coronavirus disease 2019 (COVID-19) pandemic.

Methods

A stratified random sample (n = 22,858) of SMs (Air Force, Army, Navy, and Marine Corps) who completed a questionnaire on their SRNS use and AE experiences and were still on active duty were asked to complete the identical questionnaire on a second occasion. Twenty-five percent of successfully contacted SMs completed both questionnaires (n = 5,778) and were included in this investigation. The average ± standard deviation time between questionnaires was 1.3 ± 0.2 years.

Results

Prevalence of reported SRNS use ≥1 time/week in the baseline (BL) and follow-up (FU) phases were as follows: any SRNS: BL = 46%, FU = 41%; sport drinks: BL = 31%, FU = 28%; sport bars: BL = 30%, FU = 24%; sport gels: BL = 4%, FU = 4%. Reported weekly aerobic and resistance training durations were reduced in the FU period (8% and 26%, respectively). The proportion of SMs reporting SRNS use in both study phases was as follows: any SRNS = 62%, sport drinks = 54%, sport bars = 50%, sport gels = 35%. Prevalence of reported AEs in the BL and FU phases were as follows: any SRNS: BL = 1.9%, FU = 1.9%; sport drinks: BL = 1.0%, FU = 1.3%; sport bars: BL = 1.7%, FU = 1.4%; sport gels: BL = 3.3%, FU = 2.5%. The proportion of SMs reporting AEs in both phases was as follows: any SRNS = 14%, sport drinks = 11%, sport bars = 17%, sport gels = 0%.

Conclusions

Overall SRNS use prevalence decreased slightly in the FU period, possibly because of reduced physical training related to military restrictions imposed during the emergence of COVID-19 between surveys. A large proportion of SMs reported changing their use patterns in the FU with some discontinuing use and others initiating use. The AE incidence was similarly low in the BL and FU phases, and few SMs reported AEs in both phases suggesting AEs were transitory. AE reporting for SRNSs was much lower than previously found for dietary supplements, possibly because of greater government regulatory control over SRNSs.

KEYWORDS:

• Nutrition
• gender
• age
• body mass index
• physical activity
• dietary supplements

List of Abbreviations

95% CI	=	95% confidence interval
AE	=	adverse effect
BL	=	baseline
BMI	=	body mass index
COVID-19	=	coronavirus disease 2019
FDA	=	Food and Drug Administration
FU	=	follow-up
SM	=	service member
SE	=	standard error
SRNS	=	sports-related nutritional supplement
US	=	United States

Acknowledgments

Thanks to Ms Patricia Bremner for assistance in obtaining references and Ms Lauren Thompson for editorial comments.

Disclaimer

The opinions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Army or the Department of Defense. Citations of commercial organizations and trade names in this report do not constitute an official Department of the Army endorsement or approval of the products or services of these organizations. Approved for public release; distribution is unlimited.

Disclosure statement

No potential conflict of interest was reported by the authors.

Authors’ contributions

JJK designed the research, analyzed data, wrote drafts of the paper, and had responsibility for final content; TWD designed research, conducted research, provided essential material, and had responsibility for final content; RAS analyzed data and had responsibility for final content; EKF designed research and had responsibility for final content; HRL designed research and had responsibility for final content. All authors have read and approved the final manuscript.

Ethics Approval and Consent to Participate

The Naval Health Research Center’s Institutional Review Board (protocol number NHRC.2016.0025) approved the investigation. SMs consented to participate by signing an informed consent document. Investigators adhered to policies and procedures for protection of human subjects as prescribed by Department of Defense Instruction 3216.01, and the research was conducted in adherence with provisions of 32 Code of Federal Regulations Part 219.

Availability of Data and Materials

The datasets generated and/or analyzed during the current study are not publicly available due to US government restrictions but are available from the corresponding author on reasonable request.

Additional information

Funding

This work was supported by Department of Defense Center Alliance for Nutrition and Dietary Supplement Research of the Defense Medical Research and Development Program, the US Army Medical Research and Development Command (USAMRDC).