Efficacy of a Once Daily Calcium and Vitamin D Fortified Food Product to Improve Bone Microarchitecture

Study Overview
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Brief Summary
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The primary objective of this randomized, double-blind, placebo controlled trial is to determine the efficacy of a once per day calcium (1000mg) and vitamin D (1000IU) fortified food product on bone turnover markers, including parathyroid hormone (PTH) and microarchitecture during Army basic military training (BCT). The investigators hypothesize that consumption of a once daily calcium and vitamin D fortified food product will stabilize PTH and contribute to improved bone microarchitecture compared to placebo. The results will determine the efficacy of daily supplementation with calcium and vitamin D on bone turnover markers as well as provide novel data regarding microarchitectural changes during BCT as assessed by high resolution peripheral computed tomography (HRpQCT) scanning.

Detailed Description
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Stress fractures may affect up to 2-5% of male and 8-21% of female Soldiers during training, resulting in attrition in up to 60% of affected personnel. A recent report indicates that supplemental calcium (2000mg) and vitamin D (800-1000IU) stabilizes PTH, increases tibia volumetric bone mineral density in male and female recruits undergoing Army BCT, and reduces stress fracture incidence by up to 20% in female Nacy recruits. Bone macroarchitecture has been measured in response to basic training however, the resolution of standard peripheral quantitative computed tomography (pQCT) is insufficient for assessment of microarchitectural changes, which may underlie the pathophysiology of stress fracture. With the use of HRpQCT this study will allow the investigators to evaluate microarchitectural changes within the bone tissue and assess the efficacy of a moderate daily dose of calcium and vitamin D to support bone health during BCT.

Official Title
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Efficacy of a Once Daily Calcium and Vitamin D Fortified Food Product to Improve Bone Microarchitecture in Response to Army Basic Combat Training

Conditions
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Bone Alteration, Dietary Modification

Intervention / Treatment
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* Dietary Supplement: Calcium/Vitamin D
* Dietary Supplement: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female or male US Army recruits beginning Army basic combat training at Fort Jackson, South Carolina Exclusion Criteria: Pregnant or breastfeeding History of kidney stones or kidney disease History of amenorrhea History or endocrine disorders History of bone modifying disorders Currently taking, or have taken glucocorticoid drugs in the 2 years prior to study participation Currently diagnosed as anemic by healthcare professional Those allergic to any component of the snack bar

Ages Eligible for Study
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Minimum Age: 17 Years
Maximum Age: 42 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Calcium/Vitamin D<br>Dietary supplement distributed and consumed as one calcium and vitamin D fortified snack bar per day | Dietary Supplement: Calcium/Vitamin D<br>* Daily, calcium and vitamin D fortified snack bar<br>|
| Placebo Comparator: Placebo<br>Placebo distributed and consumed as one isocaloric, unfortified snack bar per day | Dietary Supplement: Placebo<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Bone Turnover Markers | Participants will have a pre- and post- BCT blood draw | 8-10 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Bone Microarchitecture | Participants will receive a bone scan pre- and post- BCT in order to determine changes in bone microarchitecture | 8-10 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Bone, Calcium, Vitamin D, Parathyroid Hormone, Microarchitecture