What a 20-Year Study Reveals About Military Mortality

by Jon Scaccia December 18, 2024

What happens when those who serve their country return home? While much attention focuses on the visible scars of war—physical injuries, PTSD, and suicide—less is known about the broader risks to long-term health and mortality among veterans. A recent study sheds light on the factors that influence mortality in U.S. service members and veterans, offering crucial insights for public health, military leadership, and the veterans themselves.

The Study That Spanned Two Decades

The Millennium Cohort Study, the largest and longest-running health study of U.S. service members, tracked over 200,000 active-duty personnel and veterans who served during Operations Enduring Freedom, Iraqi Freedom, and New Dawn (OEF/OIF/OND). Over 20 years (2001–2021), researchers examined who thrived, who struggled, and who passed away—and why. By March 2021, 1.9% of participants (3,806 individuals) had died, with most deaths occurring after military service ended.

This expansive study aimed to uncover the factors contributing to all-cause mortality, ranging from combat exposure and deployment history to lifestyle behaviors like smoking and drinking. While the findings reveal some expected patterns, they also challenge conventional wisdom and highlight overlooked issues.

Who’s Most at Risk?

Deployment and Combat: A Mixed Picture

Deployed service members had a lower overall risk of mortality compared to those who never deployed. This finding may reflect the “healthy deployer effect,” where individuals in better physical and mental health are more likely to be sent on deployments. However, within the deployed population, those who experienced combat faced heightened risks. Combat exposure is associated with long-term physical and psychological stress, which can manifest as chronic health problems or risky behaviors like smoking and drinking.

Rank, Role, and Risk

Enlisted personnel and combat specialists—those most likely to face the harshest conditions—experienced higher mortality rates than officers and those in non-combat roles like healthcare or support services. The disparities point to occupational hazards and potential socioeconomic challenges that persist after service, such as limited access to resources or career advancement opportunities.

Stress, Health, and Lifestyle Choices

The study highlighted three key contributors to mortality:

1. Stressful Life Events: Participants who reported significant stress—such as financial difficulties, divorce, or serious illness—faced a substantially higher risk of death.
2. Health Behaviors: Smoking and problem drinking stood out as major risk factors. Smokers had a 50% increased risk of mortality compared to non-smokers.
3. Physical and Mental Health: Poor scores on physical and mental health metrics strongly predicted early mortality, underlining the importance of comprehensive care during and after military service.

Demographics and the “Hispanic Paradox”

Demographics also played a role. Women had significantly lower mortality rates than men, as did Hispanic participants compared to their White, non-Hispanic counterparts. The latter aligns with the “Hispanic Paradox,” a phenomenon where Hispanic individuals often exhibit better health outcomes despite facing socioeconomic challenges. This protective effect may stem from cultural factors, community support, or differences in health-seeking behavior.

Lessons for Public Health and Military Leadership

These findings carry significant implications for policy and practice:

1. Targeted Interventions: Programs should focus on high-risk groups, including enlisted personnel, combat specialists, and those experiencing chronic stress. Offering tailored support for smoking cessation, stress management, and mental health could save lives.
2. Strengthening the Transition to Civilian Life: With most deaths occurring after service, the post-military transition is a critical period. Expanding access to education, job training, and healthcare for veterans—particularly those with combat exposure—can mitigate long-term risks.
3. Holistic Health Monitoring: Military health systems should track not only physical injuries but also mental health and lifestyle factors. Comprehensive screening could identify at-risk individuals before problems escalate.
4. Cultural Competency in Care: The success of Hispanic service members suggests that culturally tailored interventions might be more effective in improving outcomes across diverse populations.

What’s Next?

While the study provides invaluable insights, it also raises new questions:

• How do these mortality risks evolve as the cohort ages into middle and later adulthood?
• What additional factors—like environmental exposures or access to healthcare—might explain differences in mortality risk?
• How can the findings inform policies in other nations with different military structures and healthcare systems?

Future research will be crucial to understanding the long-term health trajectories of this population. Meanwhile, the current findings offer a clear mandate for action: to not only honor service members for their sacrifice but to actively protect their health and well-being, both during and after their military careers.

Join the Conversation

This study touches on issues that affect all of us, whether we’re veterans, public health practitioners, or concerned citizens. We’d love to hear your thoughts:

1. What can communities do to better support veterans transitioning to civilian life?
2. How can public health programs address the specific needs of high-risk groups like combat veterans?
3. What lessons from this research could be applied to civilian populations facing chronic stress and health disparities?

Share your insights in the comments or join the discussion on social media.

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