Do supplements improve warfighter performance and recovery?
Writing in the journal Nutrients, researchers from military college Norwich University, Kansas University Medical Center and the Stanford Prevention Research Center shared findings from an examination of randomized and quasi-experimental controlled trials collected from the Medline and CINAHL databases published between 1990 and 2023.
“There is a critical need to understand the efficacy, dosing and safety of dietary supplements in military and tactical populations, as muscle performance and recovery outcomes are paramount for warfighters, especially when deployed or in the field where these populations are often required to perform without reliable access to a well-balanced diet,” they wrote.
Published in a special issue on nutritional status and ergogenic aids in exercise and sports performance, the study highlighted that while there is ample research into the effects of supplementation in sports athletes, it is difficult to extrapolate these outcomes to the tactical population.
Supplement use in the military
The researchers noted that training regimens equip the military to endure substantial challenges but that many service members turn to supplementation to enhance performance and aid recovery in the face of sustained exertion under often extreme conditions.
According to findings from a U.S. Military Dietary Supplement Use Study survey of 26,681 Air Force, Army, Marine Corps and Navy personnel, 74% reported using more than one dietary supplement per week, and 40% of users consumed more than five per week. Multivitamins/multiminerals were the most used supplement (45%), followed by combination products (44%), proteins/amino acids (42%), individual vitamins/minerals (31%), herbals (20%), joint health products (9%) and prohormones.
Factors associated with greater use included female sex, higher educational levels and rank, higher body mass index, greater physical activity and participation in weight control programs.
“While the appropriate use of some supplements may benefit military personnel, others may cause harm to health, performance, career and reputation,” the researchers wrote. “This is particularly salient, given a recent report that demonstrated the majority of weight loss supplements marketed to members of the military are labeled inaccurately, with some in direct violation of the Department of Defense Prohibited Dietary Supplements Ingredients List.”
They also noted that the limited data on the benefits of dietary supplementation on field outcomes in the tactical population are mostly self-reported or cross-sectional in nature.
Small benefits, significant limitations
Of the trials collected, the research team considered 16 studies: Four were conducted on protein or carbohydrate; four on beta-alanine alone, creatine alone, or in combination; two on mixed nutritional supplements; two on probiotics alone or in combination with beta hydroxy-beta methylbutyrate calcium; and four on phytonutrient extracts including oregano, beetroot juice, quercetin and resveratrol.
Ten of the studies examined outcomes related to physical performance, and six evaluated effects on injury or recovery.
“Overall, protein, carbohydrate, beta-alanine, creatine and beetroot juice modestly improved performance, while quercetin did not,” the researchers reported. “Protein, carbohydrates, beta-alanine, probiotics and oregano reduced markers of inflammation, while resveratrol did not.”
While they noted that supplementation may have small benefits on muscle performance and recovery in warfighters and that no harmful outcomes were identified in the studies reviewed, they acknowledged significant limitations in interpretation due to the largely inconsistent evidence of ingredients and comparable outcomes.
“Further interventional research, particularly in the field setting, is required to understand optimal supplemental protocols and practical differences in supplemental support during military training versus active-duty assignments,” the review concluded.
“The results of this systematic review highlight the unique challenges faced by military personnel and call for continued exploration of nutritional interventions to enhance overall resilience and physical capabilities in the complex landscape of military operations.”
Source: Nutrients
doi: 10.3390/nu16162746
“Dietary Supplementation on Physical Performance and Recovery in Active-Duty Military Personnel: A Systematic Review of Randomized and Quasi-Experimental Controlled Trials”
Authors: Jacie Harlow et al.
