Vitamin D Supplementation and Immunity/Physical Performance

Not Applicable

• Conditions: Vitamin D Status

• Registration Number: NCT03132103
• Lead Sponsor: Bangor University

Brief Summary

The purpose of this study is to examine the effect of vitamin D supplementation on vitamin D status, immunity and physical performance.

Detailed Description

Vitamin D plays a key role in bone mineralisation and has been linked to immune defence maintenance and muscle function. Vitamin D is primarily obtained from endogenous synthesis in response to skin sunlight exposure and follows a seasonal pattern; whereby, vitamin D levels peak at the end of the summer and fall to a trough during winter. If winter vitamin D levels can be increased to match those found in summer using supplementation, it is proposed sufficient vitamin D levels will improve physical performance and reduce susceptibility to illness in military recruits.

Study Timeline

• Study Start: 2016-01-06
• Study First Submitted: 2017-03-30
• Status Verified: 2017-04
• Study First Submitted QC: 2017-04-24
• Last Update Submitted: 2017-04-24
• Study First Posted: 2017-04-27
• Last Update Posted: 2017-04-27
• Primary Completion: 2017-04-28
• Study Completion: 2017-08-31

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: Male
• Target Recruitment: 260

Inclusion Criteria

• Passed medical assessment by medical doctor

Exclusion Criteria

• Medically deferred by medical doctor
• Regular sun bed use
• Holiday in a hot sunny climate in <3 months
• Regular vitamin D supplementation

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Vitamin D status	Up to 20 months	Circulating 25-hydroxy-vitamin D, 1,25-d OH(OH)D

Secondary Outcome Measures

Name	Time	Method
Physical performance 1	Up to 20 months	Vertical Jump height (cm) and peak power output (watts)
Physical performance 2	Up to 20 months	Maximal dynamic lift strength (kg)
Physical performance 3	Up to 20 months	Multi-stage fitness test predicted VO2max (mL/kg/min)
Hepatitis B antibody	Up to 20 months	Antibody produced in response to the presence of Hepatitis B antigen (e.g. Hepatitis B vaccine)
Mucosal immunity	Up to 20 months	Secretory Immunoglobulin A levels

Trial Locations

Locations (1)

Infantry Training Centre; 🇬🇧 Catterick, North Yorkshire, United Kingdom