Analysis of Select Dietary Supplement Products Marketed to Support or Boost the Immune System

IMPORTANCE

Cold, flu, and immunity dietary supplement product sales have skyrocketed since the start of the COVID-19 pandemic. Supporting or boosting the immune system has become an important reason for using dietary supplements, and many consumers are purchasing products through online platforms.

OBJECTIVES

To examine whether select dietary supplement products advertised as supporting or boosting the immune system are accurately labeled according to the Supplement Facts label of listed ingredients and to qualitatively describe the product labels' characteristics in terms of claims made.

DESIGN, SETTING, AND PARTICIPANTS

In this case series, 30 featured immune health dietary supplements were selected and purchased from Amazon.com in May 2021. Product analysis was performed using liquid chromatography-mass spectrometry. The list of ingredients detected through analysis for each product was compared with the ingredients on the product's Supplement Facts label to determine whether the product's label was accurate. Claims made on product labels were also evaluated by using the Operation Supplement Safety Scorecard's set of questions to describe the labels' characteristics.

RESULTS

A total of 30 select dietary supplement products were evaluated. Thirteen of the 30 products had accurate labels based on the product analysis. Of the 17 products with inaccurate labels, 13 had ingredients listed on the labels that were not detected through analysis, such that their labels were misbranded. Nine products had substances detected that were not claimed on the product labels, some of which may be considered adulterated. Five were misbranded and contained additional components not claimed on the label. No product had third-party certification seals present on the packaging. Ten of the 13 products with accurate labels received a score of 4 or more when applying the Operation Supplement Safety Scorecard, meaning the product was "likely okay/less risky."

CONCLUSIONS AND RELEVANCE

In this case series study, most of the products tested had inaccurate labels and claims that were inconsistent with requirements the US Food and Drug Administration has put forward for dietary supplements. Quality control measures seem to be insufficient for most of these select products, and claims made on labels may be misleading consumers who purchase products.

L-citrulline prevents heat-induced mitochondrial dysfunction and cell injury through nitric oxide-mediated Drp1 inhibition in mouse C2C12 myoblasts

Severe heat exposure causes mitochondrial fragmentation and dysfunction, which contribute to the pathogenesis of heat-related illness. L-citrulline is a naturally occurring amino acid and has been suggested to influence heat shock responses. This study aimed to test whether L-citrulline supplementation would preserve mitochondrial integrity and attenuate heat-induced skeletal muscle injury, and elucidate the underlying mechanisms. At 37°C, L-citrulline (2 mM) increased mitochondrial elongation in mouse C2C12 myoblasts, a process associated with a reduction in mitochondrial fission protein Drp1 levels. Mechanistic studies revealed that L-citrulline increased cellular nitric oxide (NO) levels, but not S-nitrosylation of Drp1. L-citrulline caused a decrease in phosphorylation of Drp1 at Ser 616 and an increase in phosphorylation of Drp1 at Ser 637, which resulted in a reduced mitochondrial localization of Drp1. L-NAME, a non-selective NO synthase inhibitor, abolished the increase in L-citrulline-induced NO levels and inhibited Drp1 phosphorylation changes and mitochondrial elongation, which indicates involvement of a NO-dependent pathway. Under 43°C heat stress conditions, L-citrulline prevented translocation of Drp1 to mitochondria, mitochondrial fragmentation and decreased membrane potential. Finally, L-citrulline pretreatment inhibited heat-induced reactive oxygen species (ROS) overproduction, caspase 3/7 activation, apoptotic cell death, and improved cell viability. NO inhibitor L-NAME abolished all the above protective effects of L-citrulline under heat stress. Our results suggest that L-citrulline prevents heat-induced mitochondrial dysfunction and cell injury through NO-mediated Drp1 inhibition in C2C12 myoblasts. L-citrulline may be an effective treatment for heat-related illnesses and other mitochondrial diseases.

Evaluating the heterogeneous effect of a modifiable risk factor on suicide: The case of vitamin D deficiency

OBJECTIVES

To illustrate the use of machine learning methods to search for heterogeneous effects of a target modifiable risk factor on suicide in observational studies. The illustration focuses on secondary analysis of a matched case-control study of vitamin D deficiency predicting subsequent suicide.

METHODS

We describe a variety of machine learning methods to search for prescriptive predictors; that is, predictors of significant variation in the association between a target risk factor and subsequent suicide. In each case, the purpose is to evaluate the potential value of selective intervention on the target risk factor to prevent the outcome based on the provisional assumption that the target risk factor is causal. The approaches illustrated include risk modeling based on the super learner ensemble machine learning method, Least Absolute Shrinkage and Selection Operator (Lasso) penalized regression, and the causal forest algorithm.

RESULTS

The logic of estimating heterogeneous intervention effects is exposited along with the illustration of some widely used methods for implementing this logic.

CONCLUSIONS

In addition to describing best practices in using the machine learning methods considered here, we close with a discussion of broader design and analysis issues in planning an observational study to investigate heterogeneous effects of a modifiable risk factor.

Go for Green® Nutrition Program: Translating Evidence Into Practice

Introduction

Go for Green® (G4G) is an evidence-based, multi-component nutrition program for military dining facilities (DFAC) to improve nutritional fitness among Service Members. The program evolved from supporting “fueling” during initial Army training into a robust intervention across all U.S. Military branches. The current G4G program consists of eight program requirements to optimize the nutrition environment, including traffic light labeling, nutritious menus, choice architecture, food promotion, marketing, and staff training. The evolution of the G4G program, development of standardized program requirements, and lessons learned are described.

Materials and Methods

The latest scientific evidence, best practices in health promotion and nutrition education, results and data from G4G implementation in the military community support the current version of G4G. Feedback and observations from program developers, military branch foodservice headquarters, installation leadership, and local G4G DFAC teams provided insight into implementation challenges, successes, facilitators, and barriers.

Results

The G4G program has evolved and expanded from its initial inception over 10 years ago to its current version. Research studies, nutrition science, and feedback from military community stakeholders have informed programmatic changes and improvements.

Conclusions

G4G 2.0 is a robust, innovative, multi-component, performance nutrition program with clear program element requirements. Value was added to elevate the G4G program by setting program requirements, expanding program components, and establishing a centralized resource hub. Performance nutrition initiatives in local military DFAC for dining facilities, such as G4G 2.0, has great potential to impact the health and well-being of Service Members.

Relative safety and quality of various dietary supplement products U.S. Service Members ask about

CONTEXT

The purpose of this project was to determine types of dietary supplement products U.S. Service Members frequently ask about and identify risks associated with select products that consumers should be aware of when considering their use.

METHODS

Forty-one dietary supplement products frequently asked about through the Operation Supplement Safety's (OPSS.org) Ask-the-Expert portal were selected. Product analysis was performed to verify whether select products were accurately labeled and to identify any risky ingredients contained in these products. Operation Supplement Safety Risk Assessment Scorecard criteria were additionally used as a screening tool to assess a product's relative safety potential.

RESULTS

Among the select dietary supplements, 12 (29.3%) were marketed as pre-workout products; 14 (34.1%) for weight loss; four (9.8%) for male enhancement/testosterone boosters; and 11 (26.8%) as body building supplements. Eleven (26.8%) products had accurate labels; only eight of these had accurate labels plus no risky ingredients listed on the labels. Twenty-six (63.4%) products were misbranded; 10 (24.4%) were adulterated, and six (14.6%) were both misbranded and adulterated. Risky ingredients appeared on 23 (56%) of all product labels. Eight of these 23 products also had additional risky ingredients not listed on the labels but detected through analysis. According to the Scorecard based on label claims, 35 (85.4%) received a rating of "no-go/risky".

CONCLUSIONS

U.S. Service Members and the public at large should be aware that dietary supplements may contain risky ingredients and know how to identify ingredients on the label to evaluate potential risk.

Analytical Challenges and Metrological Approaches to Ensuring Dietary Supplement Quality: International Perspectives

The increased utilization of metrology resources and expanded application of its' approaches in the development of internationally agreed upon measurements can lay the basis for regulatory harmonization, support reproducible research, and advance scientific understanding, especially of dietary supplements and herbal medicines. Yet, metrology is often underappreciated and underutilized in dealing with the many challenges presented by these chemically complex preparations. This article discusses the utility of applying rigorous analytical techniques and adopting metrological principles more widely in studying dietary supplement products and ingredients, particularly medicinal plants and other botanicals. An assessment of current and emerging dietary supplement characterization methods is provided, including targeted and non-targeted techniques, as well as data analysis and evaluation approaches, with a focus on chemometrics, toxicity, dosage form performance, and data management. Quality assessment, statistical methods, and optimized methods for data management are also discussed. Case studies provide examples of applying metrological principles in thorough analytical characterization of supplement composition to clarify their health effects. A new frontier for metrology in dietary supplement science is described, including opportunities to improve methods for analysis and data management, development of relevant standards and good practices, and communication of these developments to researchers and analysts, as well as to regulatory and policy decision makers in the public and private sectors. The promotion of closer interactions between analytical, clinical, and pharmaceutical scientists who are involved in research and product development with metrologists who develop standards and methodological guidelines is critical to advance research on dietary supplement characterization and health effects.

Protective effects of dietary curcumin and astaxanthin against heat-induced ROS production and skeletal muscle injury in male and female C57BL/6J mice

AIMS

This study aimed to: 1) investigate sex differences in heat-induced mitochondrial dysfunction, ROS production, and skeletal muscle injury in mice; 2) evaluate whether curcumin and astaxanthin, alone or together, would prevent those heat-induced changes.

MAIN METHODS

Male and female C57BL/6J mice were treated with curcumin and astaxanthin for 10 days, then exposed to 39.5 °C heat for up to 3 h. Heat-induced hyperthermia, changes in mitochondrial morphology and function, and oxidative damage to skeletal muscle were evaluated.

KEY FINDINGS

Although female mice had a slightly higher basal core body temperature (Tc) than male mice, peak Tc during heat exposure was significantly lower in females than in males. Heat increased ROS levels in skeletal muscle in both sexes; interestingly, the increases in ROS were greater in females than in males. Despite the above-mentioned differences, heat induced similar levels of mitochondrial fragmentation and membrane potential depolarization, caspase 3/7 activation, and injury in male and female skeletal muscle. Individual treatment of curcumin or astaxanthin did not affect basal and peak Tc but prevented heat-induced mitochondrial dysfunction, ROS increases, and apoptosis in a dose-dependent manner. Moreover, a low-dose combination of curcumin and astaxanthin, which individually showed no effect, reduced the heat-induced oxidative damage to skeletal muscle.

SIGNIFICANCE

Both male and female mice can develop mitochondrial dysfunction and oxidative stress in skeletal muscle when exposed to heat stress. High doses of either curcumin or astaxanthin limit heat-induced skeletal muscle injury, but a low-dose combination of these ingredients may increase their efficacy.

Advancing the Practice of Contemporary Military Performance Psychology:A Full-Spectrum Approach to Psychological Health and Readiness

The Department of Defense (DoD) continues to emphasize operational readiness, lethality, and optimal performance. Performance psychology is a critical aspect of and central dimension to human performance optimization in support of Preservation of the Force and Family (POTFF) and Total Force Fitness (TFF). The delivery of performance psychology services must continue to evolve to maximize its potential for enhancing combat performance and supporting psychological readiness in warfighters across all branches of service. The authors (1) provide a brief history of the evolution of military psychology; (2) explore how performance psychology complements and broadens approaches to support warfighter health and readiness; and (3) present a set of strategies to advance performance psychology services toward an aspirational model. Such strategies will more effectively promote best practices to better target operational performance, complement existing health and medical service delivery, and encompass a systems approach to sustainable training. Moreover, these strategies aim to increase return on investment of psychological readiness efforts for warfighters across all branches of service.

Prioritized research recommendations and potential solutions: addressing gaps surrounding dietary supplement ingredients for boosting brain health and optimizing cognitive performance

In the market of dietary supplements, a low level of certainty exists in the state of the science, coupled with not always knowing what is in the product. Together these issues make weighing benefits/risks difficult and hinder the ability to guide evidence-based practice decisions. The authors sought to identify priorities and develop potential solutions to address research gaps so that information disseminated, can ultimately, be relied upon, when trying to make appropriate and safe decisions. Using a modified-Delphi process, 8 panelists reviewed evidence, provided from systematic review, on dietary supplement ingredients for brain health, and prioritized gaps identified and offered potential solutions. Research gaps specific to dietary supplements research included the need for quality testing of products, the question of bioavailability and absorption of ingredients, and optimal composition and standardization of supplements under investigation. Other gaps related to populations studied; a general sense of bias towards focusing research on diseased rather than maintaining or optimizing performance in healthy populations. Additionally, the lack of uniform cognitive performance measures and metrics used across research is a gap, as well as whether the metrics are accurate representations of or even generalizable to "real-life" participants wishing to optimize their performance. Methodological quality and ethical concerns in the conduct and reporting of science encompass all issues. If resources map to potential solutions outlined in this paper, then these proposed next steps offered will help facilitate meaningful research, move evidence into practice recommendations, and ultimately develop better decision-making tools for consumers to trust and rely upon for making safe supplement decisions.

A Threat to Military Combat Power: Dietary Supplements

BACKGROUND

The use of dietary supplements by young warfighters is pervasive and comes with a readiness cost, especially in the deployed setting. Predatory targeting and marketing by various unscrupulous companies put this population at risk for a higher than baseline risk for adverse events.

METHODS

We report on 6 serious adverse events experienced by warfighters while deployed in Kuwait and Afghanistan. Presented is a discussion of current practice gaps and solutions, as well as details regarding how polypharmacy contributes to the seriousness of the threat posed by problematic supplements.

RESULTS

The morbidity associated with the 6 cases of dietary supplement adverse events compromised mission readiness and was costly in terms of health and health care expenditures.

CONCLUSION

The military dietary supplement issue needs exposure, review, and action at the highest levels of government.

Baseline Aerobic Fitness in High School and College Football Players: Critical for Prescribing Safe Exercise Regimens

BACKGROUND

Nontraumatic fatalities occur on a regular basis in high school (HS) and college football athletes, primarily in obese linemen performing high-intensity exercise. One contributing factor to these deaths may be a mismatch between baseline aerobic (cardiorespiratory) fitness and exercise regimens.

HYPOTHESIS

There is a wide range of aerobic fitness in HS and college football players. Body mass index (BMI) is a safe and simple method for estimating baseline aerobic fitness.

STUDY DESIGN

Retrospective cohort study.

LEVEL OF EVIDENCE

Level 3.

METHODS

A retrospective review was performed on 79 HS football athletes who had VO_2Peak (mL·kg^-1·min^-1) measured during the offseason. Multivariate regression analysis was used to determine if BMI (obese, overweight, and normal; kg/m²), position played (linemen vs other), year in school (freshmen vs other), and/or race (African American vs White) were risk factors for poor aerobic fitness. A separate cohort of 135 (48 HS; 87 college) football athletes performed a 6-minute run test to determine speed (miles/min), extrapolate VO_2Max, and calculate reference values for suggested upper threshold safe starting speeds (85% of maximum) for aerobic training based on BMI. The relationship between BMI and VO_2Peak was assessed. The exercise regimens (speeds) of 2 collegiate football fatalities from the public domain were used to predict their VO_2Max values.

RESULTS

Mean VO_2Peak (mL·kg^-1·min^-1) was 38.5 ± 8.6 (range 19.1-60.6); when grouped by BMI, low scores (<40) were found in 87.5% of obese (32.4 ± 7.7), 47.8% of overweight (40.8 ± 7.6), and 45.2% of normal (41.4 ± 7.8) athletes. VO_2Peak was significantly lower in linemen (32.8 ± 6.4; P = 0.007) compared with nonlineman (41.8 ± 7.9), and in obese players (by BMI; 32.4; P = 0.019) compared with nonobese players (41.4 ± 7.6), but did not differ by age, year in school, or race. Means for speed (min/mile) and extrapolated VO_2Max (mL·kg^-1·min^-1) for the 6-minute run test by BMI groups were both significantly different (P = 0.001) for normal (7.0 ± 0.6; 51.1 ± 2.6), overweight (7.6 ± 0.8; 46.5 ± 3.2), and obese (8.9 ± 1.5; 36.8 ± 5.9) athletes. There was a significant negative correlation (r = -0.551; P = 0.001; R² = 0.304) between VO_2Peak and BMI. Safe starting speed recommendations for running 1 mile range from 7.3 to 12.1 min/mile for BMIs 20 to 40 kg/m² for HS and college athletes. For the 2 fatalities (mean, BMI of 36.5 kg/m²) repetitive sprint speeds were 49 and 89% higher than our safe starting speeds for their BMI.

CONCLUSION

A large spectrum of baseline aerobic fitness was noted in HS and college football players. Obese players and linemen had statistically lower baseline aerobic fitness, a major risk factor for possible heat illness. BMI is an acceptable surrogate for VO_2Peak and can be employed to develop safe training regimens without the need for a maximum fitness test, which can place the athlete at risk for a medical event.

CLINICAL RELEVANCE

Knowledge of BMI provides an estimate of baseline aerobic fitness and a foundation for prescribing safe, individualized exercise regimens.

Self-Reported Health Indicators in the US Army: Longitudinal Analysis From a Population Surveillance System, 2014‒2018

Objectives. To describe health-related behaviors or indicators associated with overall health and well-being using the Global Assessment Tool (GAT), a health behavior and psychosocial questionnaire completed annually by US Army personnel. Methods. We analyzed GAT responses from 2014 to 2018, consisting of 367 000 to 449 000 respondents per year. We used generalized estimating equations to predict the presence of each health behavior or indicator, aggregated by year and stratified on various demographics. Results. Key findings included decreases from 2014 to 2018 in risky health behaviors such as hazardous drinking (7.5% decrease) and tobacco use (7.9% decrease), dietary supplement use (5.0% to 10.6% decrease, depending on type), self-reported musculoskeletal injury (5.1% decrease), and pain interference (3.6% decrease). Physical activity, sleep, and nutritional habits largely remained consistent over time. Conclusions. In the Army, tobacco, alcohol, and risky dietary supplement usage appears to be declining, whereas lifestyle health behaviors have been stable. Whether these trends reflect responses to health education is unknown. The GAT provides useful insights into the health of the Army, which can be leveraged when developing health-related educational programs and policies. Public Health Implications. Health behaviors that have changed less over time (e.g., nutrition, sleep) may require novel approaches compared with those that changed more (e.g., dietary supplement use, drinking). (Am J Public Health. 2021;111(11):2064-2074. https://doi.org/10.2105/AJPH.2021.306456).

Perceptual strain in a compensable hot environment: Accuracy and clinical correlates

Heat strain monitoring indexes are important to prevent exertional heat illness (EHI) and uncover risk factors. Two indexes are the Physiological Strain Index (PSI) and a subjective PSI analogue, the Perceptual Strain Index (PeSI). The PeSI is a feasible alternative to PSI in field conditions, although the validity has been variable in previous research. However, the PeSI has been rarely examined at a low heat strain with compensable heat stress, such as during a heat tolerance test (HTT). This study evaluated the discrepancy between the maximal PeSI and maximal PSI achieved during a HTT and determined their association with EHI risk factors, including history of EHI, percent body fat (%BF), relative VO_2max, fatigue and sleep status (n = 121; 47 without prior EHI, 74 with prior EHI). The PSI was calculated using the change in rectal temperature (T_re) and heart rate (HR) and PeSI was calculated based on the formula containing thermal sensation (TS), a T_re analogue, and rate of perceived exertion (RPE), a HR analogue. Significant associations were identified between PSI and PeSI and between PSI_HR and PeSI_HR in the total sample and between PSI and PeSI in the EHI group. Bland-Altman analyses indicated PeSI underestimated PSI in the total sample, PSI_HR was greater than PeSI_HR, and that PSI_core and PeSI_core were not significantly different, but values varied widely at different heat strains. This indicates the use of RPE underestimates HR and that the accuracy of TS to predict T_re may be subpar. This study also demonstrated that participants with higher %BF have a decreased perception of heat strain and that post-fatigue, sleep status and a prior EHI may increase the perception of heat strain. Overall, these results suggest that PeSI is a poor surrogate for PSI in a compensable heat stress environment at low heat strain.

An investigation of sickle cell trait, body mass index, and fitness in relation to venous thromboembolism among African American adults

BACKGROUND

The relationships of sickle cell trait (SCT), body mass index (BMI), and physical fitness to venous thromboembolism (VTE) in young adults have received little attention.

OBJECTIVES

To test for associations among SCT, BMI, fitness, and VTE.

PATIENTS/METHODS

We conducted a retrospective cohort study of 48,316 SCT-tested, African American individuals in the US Army during 2011-14. We used Cox proportional hazards models to compute adjusted hazards of deep vein thrombosis (DVT) and pulmonary embolism (PE) associated with selected factors.

RESULTS

Incidence rates of DVT and PE were 1.09 and 0.91 cases per 1000 person-years, respectively. Adjusted hazard ratios (aHRs) for DVT for men and women with SCT were 0.9 (95% confidence interval [CI]: 0.4-2.0; P = .711) and 1.51 (CI: 0.7-3.2; P = .274), respectively. aHRs for PE for SCT+ men and women were 1.1 (CI: 0.5-2.4; P = .773) and 1.2 (CI: 0.5-3.1; P = .650), respectively. Low physical fitness was associated with DVT and PE in women (DVT aHR =3.1; CI: 1.4-6.5; P = .004; PE aHR =4.6; CI: 2.1-9.9; P < .001) and DVT in men (aHR =2.2; CI: 1.0-4.6; P = .048). Recent weight gain of 1 or more BMI points was associated with DVT in men (aHR =1.8; CI: 1.1-2.8; P = .017).

CONCLUSIONS

We found no evidence of increased VTE risk associated with SCT in this population. However, lower fitness levels and BMI increases were so associated.

Dietary Supplement Ingredients for Optimizing Cognitive Performance Among Healthy Adults: A Systematic Review

Background: Dietary supplements promoted for brain health and enhanced cognitive performance are widely available. Claims made for these products are directed not only to the elderly wishing to prevent or mitigate cognitive decline, but also young healthy populations looking to boost their cognitive performance. It is unclear whether these claims made on product bottles and through advertising match the science. Objectives: To explore the evidence on the efficacy and safety of single dietary supplement ingredients frequently marketed with claims of enhanced cognitive performance among healthy adults. Design: A systematic review. Results: Nine of 54 dietary supplement ingredients identified through a scoping review met the eligibility criteria with at least 3 published studies identified per ingredient, yielding 69 unique publications. Ingredients evaluated included Bacopa monnieri, choline, creatine, omega-3 fatty acids, Ginkgo biloba, ginseng, Rhodiola rosea, tyrosine, and valerian root, all in supplement form and compared with a placebo, at various serving sizes and durations of use. Conclusions: The low level of certainty in the state of the science, coupled with not always knowing what is in a dietary supplement product, make weighing risks and benefits difficult; these data hinder the ability to develop recommendations about using such ingredients for consumers interested in boosting their cognitive performance. Whereas certain trends regarding promising serving sizes or duration for use, are pointed to in this synthesis, when combined, studies are inconsistent and imprecise, and many are methodologically flawed. Potential solutions to address research gaps are offered, for future research next steps, which is needed to strengthen the evidence and inform decisions.

Female Military Officers Report a Desire for Menstrual Suppression During Military Training

INTRODUCTION

Service women face female-specific challenges that present physiological and logistical burdens and may impact readiness. The stress of training can change menstrual patterns and symptoms, and limited access to hygienic, private facilities can hinder menstrual management. Therefore, suppressing menses with continuous hormonal contraception may be of interest.

MATERIALS AND METHODS

The 9-item "Military Women's Attitudes Toward Menstrual Suppression." questionnaire was administered to female officers upon entry (baseline) and graduation (post) from a 6-month secondary training course. Respondents rated their attitudes about menstruation and the stress of training, the desire for menstrual suppression, and the logistical burden of menstruation on a 1 (strongly agree) through 5 (strongly disagree) scale. Wilcoxon Signed Rank Tests determined changes in the distribution of responses from baseline to post.

RESULTS

Female officers (n = 108) completed baseline and post questionnaires (age 25.2 ± 0.3 years). At baseline, the majority disagreed/strongly disagreed that the stress of training "makes periods worse than usual" (n = 77, 71%), "increases menstrual symptoms and bleeding" (n = 77, 71%), or "magnifies premenstrual syndrome" (PMS; n = 69, 64%). Although 50% (n = 54) agreed/strongly agreed that "stopping periods while women are training is a good idea," 37% (n = 40) disagreed/strongly disagreed. The majority agreed/strongly agreed that menstrual suppression would prevent "the worry about menstrual supplies" (n = 75, 70%) and "the inconvenience of having a period during training" (n = 69, 64%). Many agreed/strongly agreed that it is difficult to deal with periods during training because "there is no privacy" (n = 52, 48%), "the inability to find adequate facilities" (n = 70, 65%), and "the lack of opportunity to use adequate facilities" (n = 52, 48%). Opinions remained largely consistent from baseline to post.

CONCLUSIONS

The desire for menstrual suppression among service women during training is high. Military health care providers should be prepared to counsel service women about strategies to manage menstruation, including the efficacy of continuous hormonal contraception for menstrual suppression. Future studies investigating benefits or risks of continuous hormonal contraception for menstrual suppression in service women should inform the clinical recommendations.

Clinical Practice Guidelines for Exertional Rhabdomyolysis: A Military Medicine Perspective

ABSTRACT

Exertional rhabdomyolysis (ER) is an uncommon condition with a paucity of evidence-based guidance for diagnosis, management, and return to duty or play. Recently, a clinical practice guideline for diagnosis and management of ER in warfighters was updated by a team of military and civilian physicians and researchers using current scientific literature and decades of experience within the military population. The revision concentrated on challenging and controversial clinical questions with applicability to providers in the military and those in the greater sports medicine community. Specific topics addressed: 1) diagnostic criteria for ER; 2) clinical decision making for outpatient versus inpatient treatment; 3) optimal strategies for inpatient management; 4) discharge criteria; 5) identification and assessment of warfighters/athletes at risk for recurrent ER; 6) an appropriate rehabilitative plan; and finally, 7) key clinical questions warranting future research.

Serum Fatty Acid Latent Classes Are Associated With Suicide in a Large Military Personnel Sample

OBJECTIVE

Fatty acids (FAs) are involved in the functioning of biological systems previously associated with suicidal behavior (eg, monoamine signaling and the immune system). We sought to determine (1) whether observed FA levels in a sample of military suicide decedents and living matched controls were consistent with latent classes having distinctive FA profiles and (2) whether those latent classes were associated with suicide and mental health diagnoses.

METHODS

Serum samples from 800 US military suicide decedents who died between 2002 and 2008 and 800 demographically matched living controls were selected at random from a large military serum repository and assayed for 22 different FAs. A latent class cluster analysis was performed using values of 6 FAs previously individually associated with suicide. Once the latent classes were identified, they were compared in terms of suicide decedent proportion, demographic variables, estimated FA enzyme activity, diagnoses, and mental health care usage.

RESULTS

A 6-latent class solution best characterized the dataset. Suicide decedents were less likely to belong to 2 of the classes and more likely to belong to 3 of the classes. The low-decedent classes differed from the high-decedent classes on 9 FAs and on estimated indices of activity for 3 FA enzymes: 14:0, 24:0, 18:1 n-9, 24:1 n-9, 22:5 n-3, 22:6 n-3, 20:2 n-6, 20:4 n-6, 22:5 n-6, elongation of very long chain fatty acids protein 1 (ELOVL1), ELOVL6, and Δ9 desaturase. The FA profiles of the latent classes were consistent with biological abnormalities previously associated with suicidal behavior.

CONCLUSIONS

This study suggests the utility of methods that simultaneously examine multiple FAs when trying to understand their relationship with suicide and psychiatric illness.

A nature-based health intervention at a military healthcare center: a randomized, controlled, cross-over study

We describe a mixed qualitative and quantitative research study in a military facility regarding the role of nature in well-being. Study intervention included two 20-minute walks. One walk was in an intentionally designed woodland environment (Green Road) and the other was on a busy campus road in a medical treatment facility (Urban Road). Twelve volunteers from a military facility participated in both walks in a cross-over experimental design. The two walking sessions were randomly ordered and preceded by pre-walk instructions appropriate to each road’s characteristics and incorporated focused attention and present moment orientation. A semi-structured post-walk interview, the primary outcome, was conducted after the conclusion of each walk. Qualitative data analyses consisted of sentiments and themes by using NVivo 12 software. The Green Road was unanimously rated as positive (100%). Responses to Urban Road were evenly distributed among positive (33.3%), negative (33.3%), and neutral/mixed (33.3%) sentiments. The Green Road yielded predominantly positive themes such as enjoyment of nature, relaxation, and feelings of privacy and safety. Urban Road produced significantly more negative themes such as concerns for safety, dislike of noise and other noxious experiences. Quantitative assessment of distress and mindfulness with Distress Thermometer (DT) and Mindful Attention Awareness Scale-state version (MAAS) demonstrated that a walk on the Green Road significantly decreased distress and increased mindfulness compared to a walk on the Urban Road. We also observed that pre-walk instructions could direct attention to both obvious and subtle elements of experience and enhance awareness. Results support the notion that an intentional nature-based environment may produce significantly more positive experiences and result in health-promoting benefits in a military health-care setting compared to an urban environment. Future studies with clinical populations could advance our understanding of the healing value of nature-based interventions. The impact of intentional green environments may be enhanced by well-designed instructions for both recreational and therapeutic use.