Evaluation of Calcium and Vitamin D Supplementation During Marine Corps Training (MCRD-PI)

United States Army Research Institute of Environmental Medicine

Status: Completed

Conditions: Bone Health; Nutrition Status

Treatments: Dietary Supplement: Calcium/Vitamin D; Dietary Supplement: Placebo

Study type: Interventional

Funder types: Other U.S. Federal agency

Identifiers

NCT02636348

15-21-HC

Details and patient eligibility

About

The primary objective of this randomized, double-blind, placebo-controlled trial is to determine the efficacy and effectiveness of Ca and vitamin D supplementation provided daily throughout Marine Corps recruit training on maintenance of PTH and indices of bone strength in Marine Corps recruits. The investigators hypothesize that Ca+D will prevent elevations in PTH and result in greater increases in indices of bone strength compared to placebo.

Full description

Military recruits undergoing initial military training (IMT) are 17 times more likely to develop stress fractures compared to active duty service members. Up to 800 male and female recruits will be enrolled at the MCRD, Parris Island, SC over two seasons (summer/fall and winter/spring) in order to account for seasonal variation in vitamin D status. Ca (2000 mg/d) and vitamin D (1000 IU/d) will be supplied as either capsules or a fortified food product daily throughout training. This study will provide novel data for the military, medical and scientific communities regarding the relationship between Ca and vitamin D supplementation and biomarkers of immune function, and the requirements for calcium and vitamin D to support bone health during IMT.

Enrollment: 380 patients

Sex: All

Ages: 17+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Male or female Marine Corps recruit at least 17 years of age.

Exclusion criteria

• Pregnant or breastfeeding
• History of kidney stones or kidney disease
• History of endocrine disorders
• Allergies to any component of the food product bar

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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380 participants in 4 patient groups, including a placebo group

Calcium/Vitamin D Bar

Experimental group

Description:

Dietary supplement consumed as 2 calcium and vitamin D fortified snack bars per day

Treatment:

Dietary Supplement: Calcium/Vitamin D

Calcium/Vitamin D Pill

Experimental group

Description:

Dietary supplement consumed as several capsules per day

Treatment:

Dietary Supplement: Calcium/Vitamin D

Placebo Bar

Placebo Comparator group

Description:

Placebo consumed as 2 isocaloric, unfortified snack bars per day

Treatment:

Dietary Supplement: Placebo

Placebo Pill

Placebo Comparator group

Description:

Placebo consumed as several capsules per day

Treatment:

Dietary Supplement: Placebo