Clinical relevance of optimizing vitamin d status in soldiers to enhance physical and cognitive performance
J Spec Oper Med. 2014 Spring;14(1):58-66.
Wentz LM, Eldred JD, Henry MD, Berry-Caban CS.
Vitamin D deficiency initiates a loss of combat effectiveness by impairing physical and cognitive functioning of combat Operators.
Synthesized in response to sunlight and consumed in the diet, vitamin D functions as a hormone and regulates gene expression for nearly 300 genes throughout the human body.
These target genes are involved processes essential to combat operations, such as
- immune function,
- response to stress,
- inflammation, and
- regulation of calcium movement.
Since widespread vitamin D deficiency is observed across the U.S. population, poor vitamin D status is expected in Servicemembers.
Physical conditions linked to vitamin D deficiency include increased risk for muscle or bone injury, muscle weakness, and reduced neuromuscular function.
Hormonally, vitamin D levels have been positively correlated with testosterone levels.
Vitamin D deficiency is also associated with
- cognitive decline,
- depression, and
- may prolong recovery following mild traumatic brain injury (mTBI).
Since vitamin D deficiency elevates systemic inflammation, poor vitamin D status at the time of brain injury may prolong the inflammatory response and exacerbate postconcussive symptoms.
Furthermore, veterans with mTBI experience chronic endocrine dysfunction.
While vitamin D status has not been assessed post-mTBI, it is plausible that vitamin D levels are altered along with testosterone and growth hormone, raising the question of whether vitamin D deficiency results from trauma-related hormonal abnormalities or whether vitamin D deficiency increases the risk for endocrine dysfunction.
Through its association with testosterone production, vitamin D deficiency may increase the risk for posttraumatic stress disorder (PTSD) since testosterone levels are altered in veterans with PTSD. Therefore, vitamin D status has a significant impact on Operator health and performance. Supplementing vitamin D to deficient Operators provides a noninvasive and low-cost intervention to maintain combat force.
PMID: 24604440  Download the PDF from ResearchGate via Vitamin D Life
- Prevalence of Vitamin D Deficiency and Its Effects on Military Forces' Performance-A Review Study - in Farsi not English
- Correlations between Vitamin D Concentrations and Lipid Panels in Active Duty and Veteran Military Personnel - 2016
- Vitamin D correlation with testosterone concentration in male US soldiers and veterans - 2016
- Fatty Acid Blood Levels, Vitamin D Status, Physical Performance, Activity, and Resiliency: A Novel Potential Screening Tool for Depressed Mood in Active Duty. . . - 2016, free PDF
- Vitamin D Clinical Relevance in the Recovery From Traumatic Brain Injury Among the Military Population
- Significance of vitamin D to tactical athletes - 2014
MILITARY MEDICINE, 181, 9:1163, 2016
COL Albert F. DiNicola, MC USAR (Ret.)*; Peter J. DiNicola, BS f; Lucia Sanchez*
*Pinnacle Medical Group, 8110 Mango Avenue, Fontana, CA 92335.
f University of California, Riverside, 900 University Avenue, Riverside, CA 92521.
Vitamin D is a necessary component in repairing bone damage, decreasing predisposition to bone injury, and strengthening the immune system. Vitamin D deficiency plays a key role in the etiology of bone pathologies such as rickets, osteoporosis, and osteomalacia. In military personnel, as noted by the Deployment Health Clinical Center, low vitamin D blood levels have been associated with
- musculoskeletal injuries and stress fractures
as well as implicated in increased susceptibility to
- chronic musculoskeletal pain,
- autoimmune disease,
- immune system dysfunction,
- diabetes, and
- post-traumatic stress disorder-mild traumatic brain injury symptoms.
Deployed Operation Iraqi Freedom/Operation Enduring Freedom military personnel have a predisposition to low vitamin D levels as a result of lack of sun exposure due to uniform sleeve worn down, shade-cover-seeking behaviors, nighttime operational requirements, use of sunblock, and lack of fortified dairy products in MREs (Meals Ready to Eat). Heavy field loads, carried by Service Members and weighing 60-100 plus pounds, also increase the risk of musculoskeletal injuries.
The intent in our study is to demonstrate the suboptimal blood vitamin D levels in apparently well-appearing adolescents and thus support the need for the military to routinely screen for and treat vitamin D deficiency and insufficiency so as to optimize bone health, reduce the risk of musculoskeletal injuries, and enhance immune system function. In our study, 120 adolescents were randomly screened during routine adolescent well checks for vitamin D deficiency (25-hydroxy blood vitamin D levels 0-19.9 ng/mL) and vitamin D insufficiency (25-hydroxy blood vitamin D levels 20.0-29.9 ng/mL). Age ranges were 11-18 years with a mean age of 14.6 years with 53% males (63/120) and 47% females (57/120). Ethnicities, in this predominantly low middle-income class population, were 95% Hispanic, 4% Caucasian, and 1% Middle Eastern with vitamin D levels obtained from May 2015 to February 2016.
Results were as follows:
- total number of patients with vitamin D deficiency and insufficiency 80% (95/120),
- total number with vitamin D deficiency 32% (38/120),
- total number with vitamin D insufficiency 48% (57/120),
- total number of males with vitamin D insufficiency 56% (35/63) and deficiency 17% (11/63), and
- total number of females with vitamin D insufficiency 39% (22/57) and deficiency 47% (27/57).
The average 25-hydroxy vitamin D deficiency and insufficiency levels were 14.7 ng/mL and 23.4 ng/mL, respectively. Our results demonstrate a high incidence of vitamin D deficiency and insufficiency levels in both adolescent males and females with the percentage of vitamin D deficiency and insufficiency in females (86%, 49/57) greater than in males (73%, 46/63).
In conclusion, more studies are needed to determine the prevalence of suboptimal vitamin D levels among military personnel and the general population, and possible links to other medical conditions, such as
- nonhealing fractures,
- chronic pain,
- depression, and
- post-traumatic stress disorder-mild traumatic brain injury.
Mandatory vitamin D levels should be routinely obtained on all military personnel especially those in pre- and postdeployment mobilization phases. Obtaining blood vitamin D levels are widely available, rapid, inexpensive, and reliable.
- Vitamin D levels continue to fall: Canada 6 percent drop from 2009 to 2011 – Feb 2013
- Only half as many people had >30 ng of vitamin D 16 years later - 2004
- Vitamin D trials by military – all 4 found benefit – review Sept 2019
- No military trainee consumed Vitamin D RDA (most were also low in Magnesium) – July 2018
- Large decreases in Vitamin D and Iron during military basic training – March 2017
- Suicide 2X more likely with low vitamin D (in military) – Jan 2013
- Military in hot climates and vitamin D deficiency - 2010
- VA found less testing for vitamin D resulted in increased health costs – Jan 2012
- 5,000 IU Vitamin D daily resulted in many benefits after 3 months (US soldiers) – RCT March 2019
- Need for Routine Vitamin D Screening in Military Personnel – Sept 2016
- US Army learning about benefits of vitamin D to trauma – Dec 2013 talking with Dr. Matthews
- Huge increase in Vitamin D supplementation in the US military (2005-13) – Oct 2016 - taking Vitamin D supplements
- Vitamin D levels have been crashing since 1995 (Polish Children, Elite Military, etc)
Brain and trauma
- Mild Traumatic Brain Injury reduced by Vitamin D – May 2014 by Wentz
- Vitamin D aided progesterone in reducing traumatic brain injury – RCT Dec 2012
- Traumatic brain injury treated by Vitamin D Progesterone Omega-3 and glutamine – May 2013
- Concussions (traumatic brain injury) getting big press coverage, vitamin D might be both a cause and a solution
Bone and Muscle
- Perhaps Stress fractures 2X less frequent if 4000 IU of vitamin D – June 2011
- Increased Bone strength during military training – with just 800 IU of vitamin D and Calcium – RCT April 2014
- Stress fractures in basic training associated with 2.5 ng less vitamin D – meta-analysis Nov 2014
- Vitamin D provides faster recovery after muscle overuse – April 2013
- Muscle inflammation 17X more probable if vitamin D deficient – Feb 2013
Overview Sports and vitamin D has the following summary
Athletes are helped by vitamin D by:
- Faster reaction time
- Far fewer colds/flus during the winter
- Less sore/tired after a workout
- Fewer micro-cracks and broken bones
- Bones which do break heal much more quickly
- Increased VO2 and exercise endurance Feb 2011
- Indoor athletes especially need vitamin D
- Professional indoor athletes are starting to supplement with vitamin D or use vitamin D beds
- Olympic athletes have used UV/vitamin D since the 1930's
- The biggest gain from the use of vitamin D is by those who exercise less than 2 hours per day.
- Reduced muscle fatigue with 10,000 IU vitamin D daily
- Muscle strength improved when vitamin D added: 3 Meta-analysis
- Reduced Concussions
See also: Sports and Vitamin D category
- Femoral and tibial stress fractures associated with vitamin D insufficiency J R Army Med Corps, March 2014
- Correction: Low Vitamin D Status and Suicide: A Case-Control Study of Active Duty Military Service Members. Sept 2013 full text online
- Bone Mineral Density Loss Following Combat-Related Lower Extremity Amputation Aug 2013
- Diet, physical activity, and bone density in soldiers before and after deployment. April 2013
- Vitamin D status, dietary intake, and bone turnover in female Soldiers during military training: a longitudinal study. Aug 2012
- Army conducting joint study to improve bone health in military personnel Jan 2014
- Anabolic Adaptations Occur in Conscripts During Basic Military Training Despite High Prevalence of Vitamin D Deficiency and Decrease in Iron Status - March 2017 =% who were Vitamin D deficient increased during training (< 20 ng): 43% Week1, 81% in week10, 92% week25
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