Clinical trial NCT01617109: Optimizing Vitamin D Status During Initial Military Training
Official title: Optimizing Vitamin D Status During Initial Military Training: A Randomized, Double-blind, Placebo-controlled Trial
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Bone Health
Nutrition Status
Keywords: Vitamin D
Calcium
Parathyroid hormone
Bone
Bone formation
Bone resorption
Micronutrients
Trace Elements
Lead sponsor: United States Army Research Institute of Environmental Medicine
Sponsor class: FED
First posted: 2012-06-12
Enrollment: 342
Sex: ALL
Minimum age (years): 17
Maximum age (years): 42
Standard ages: CHILD
ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: The primary objective of this randomized, double-blind, placebo-controlled trial is to determine the effect of vitamin D and calcium supplementation (800IU and 2000mg, respectively) on biochemical indicators of nutritional status and bone health in military personnel during Army basic combat training (BCT) and Air Force basic military training (BMT).

The investigators hypothesize that daily supplementation with vitamin D and calcium during military training will improve vitamin D status, stabilize PTH levels, and result in improvements in markers of bone health. As a result of the investigators study design, the findings will provide critically important data regarding the concentration of vitamin D in blood necessary to stabilize PTH levels and to optimize bone formation during initial military training.

Detailed description: Vitamin D is an essential nutrient for maintaining bone health. Previous work from our laboratory indicates that vitamin D status may decline in Soldiers during BCT, even during the summer months in the Southeastern United States. Stress fractures may affect up to 5% of male and 21% of female Soldiers during training, resulting in attrition in up to 60% of affected personnel, but a recent report indicates that vitamin D and calcium supplementation may attenuate stress fracture risk by up to 20% in female Navy recruits. However, biochemical measures of nutritional status and associated markers of bone health were not collected in that study, leaving questions regarding the vitamin D and calcium requirements for military personnel during periods of elevated bone turnover.

Eligibility criteria: Inclusion Criteria:

* Female or male US Army or US Air Force Recruits
* Participating in Basic Combat Training or Basic Military Training, respectively

Exclusion Criteria:

* Pregnant or breastfeeding
* History of kidney stones or kidney disease

Primary outcomes:
measure: Serum PTH pg/ml
timeFrame: Participants will be followed for the duration of basic combat training or basic military training, which are 7-9 weeks
Secondary outcomes:
Other outcomes:
Locations:
city: Fort Sill
country: United States
facility: Fort Sill
state: Oklahoma
city: San Antonio
country: United States
facility: Lackland Air Force Base
state: Texas
Study officials:
affiliation: US Army Research Institute of Environmental Medicine
name: James P McClung, Ph.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Andersen NE, Karl JP, Cable SJ, Williams KW, Rood JC, Young AJ, Lieberman HR, McClung JP. Vitamin D status in female military personnel during combat training. J Int Soc Sports Nutr. 2010 Dec 14;7:38. doi: 10.1186/1550-2783-7-38.
citation: Nakayama AT, Lutz LJ, Hruby A, Karl JP, McClung JP, Gaffney-Stomberg E. A dietary pattern rich in calcium, potassium, and protein is associated with tibia bone mineral content and strength in young adults entering initial military training. Am J Clin Nutr. 2019 Jan 1;109(1):186-196. doi: 10.1093/ajcn/nqy199.
citation: Lutz LJ, Gaffney-Stomberg E, Karl JP, Hughes JM, Guerriere KI, McClung JP. Dietary Intake in Relation to Military Dietary Reference Values During Army Basic Combat Training; a Multi-center, Cross-sectional Study. Mil Med. 2019 Mar 1;184(3-4):e223-e230. doi: 10.1093/milmed/usy153.
citation: Gaffney-Stomberg E, Lutz LJ, Rood JC, Cable SJ, Pasiakos SM, Young AJ, McClung JP. Calcium and vitamin D supplementation maintains parathyroid hormone and improves bone density during initial military training: a randomized, double-blind, placebo controlled trial. Bone. 2014 Nov;68:46-56. doi: 10.1016/j.bone.2014.08.002. Epub 2014 Aug 10.