Dietary Vitamin K2 Intake, Musculoskeletal Injury, and Cardiometabolic Health in Service Members

Background: Vitamin K2 (K2) research has demonstrated that with sufficient K2 intake, vitamin K-dependent proteins are activated to regulate bone diseases and inflammation-related diseases, offering an innovative strategy to address ongoing musculoskeletal injury (MSKi) and high adiposity challenges that threaten health promotion, performance, and readiness in service members (SMs). Objective: This study aimed to characterize K2 status in a military sample and explore the relationship between dietary K2 intake and bone health, metabolic health, and inflammation status in the context of SM health and operational readiness or deployability. Methods: At baseline and 12 months, Army and Air Force units provided data from demographic and food frequency questionnaires, body composition, bone density, cardiometabolic, and biomarker measurements. Activity trackers monitored physical activity and sleep duration continuously. Results: Between August 2023 and July 2024, we enrolled 47 active duty SMs. The sample was predominantly male, racially and ethnically diverse, averaged 27 years of age, and had an average of 6.5 years of service. At baseline, 45% met the criteria for stage I hypertension and 45% exceeded military body fat standards. Participants reported insufficient baseline dietary intake of vitamin K1+K2 and vitamin D. Over the 12 months, fermented food consumption slightly increased, activity behaviors remained unchanged, and participants self-reported 10 noncombat MSKis. Participants reported no significant changes in body composition, body fat specifically, or dietary intake of vitamin D or vitamin K2. Exploratory proteomics analysis identified links between K2 and inflammation, bone architecture, glucose homeostasis, and insulin receptors. Discussion: MSKi, high body fat, and meeting optimal nutrition goals remain readiness challenges for SMs. Exploring K2 identified meaningful metrics and actionable strategies to address these challenges. Highlighting data-informed interventions adds to nursing’s nutritional and cardiometabolic knowledge base and clinical interventions, as the nursing workforce is positioned to influence every step of patient care: conducting research, generating data to inform clinical practice and interventions, and ensuring evidence-based patient education and counseling to optimize SM health and readiness.