Related Experiment Video
Updated: Jan 19, 2026

Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
Published on: May 1, 2018
The relationship between vitamin D status and depression in a tactical athlete population
Kelly A Schaad1,2, Asma S Bukhari3,4, Daniel I Brooks5
1U.S. Baylor Military Graduate Program in Nutrition, 3630 Stanley Road, San Antonio, TX, 78234, USA. kelly.a.schaad.mil@mail.mil.
Background:
Stressors inherent to the military, such as combat exposure, separation from family, and strenuous training, collectively contribute to compromised psychological resilience and greatly impact military performance.
Methods:
This retrospective review of records was conducted to determine whether vitamin D status was associated with diagnoses of depression and if diagnoses differed by geographic location.
Results:
Depression (defined using diagnostic codes) was more prevalent in individuals who were diagnosed with vitamin D deficiency (20.4%) than in individuals who were not (4.2%). After adjustment, vitamin D deficient diagnoses remained significantly associated with depression diagnoses (OR = 1.22; 95% CI, 1.11-1.33, p < 0.001). Furthermore, vitamin D deficient diagnoses were strongly associated with geographic latitude (r2 = 0.92, p = 0.002).
Conclusion:
These results suggest that service members stationed at installations located at northerly latitudes may be at increased risk for vitamin D deficiency. Furthermore, vitamin D deficient service members may be at higher risk for diagnosis of depression. As a number of military service members avoid reporting symptoms or seeking treatment, vitamin D status may be a useful screening tool to identify service members at risk for depression.
Related Concept Videos
07:30Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
11:32A Neuroscientific Approach to the Examination of Concussions in Student-Athletes
Vitamins
Long-term Depression
Relationship Formation
10:31A Multi-Modal Approach to Assessing Recovery in Youth Athletes Following Concussion

