The Effect of Vitamin D Supplements on Vitamin D Status, Cardiometabolic Health and Immune Defense in Danish Children

Study Overview
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Brief Summary
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The main purpose of this study is to investigate whether and in which doses vitamin D intake is needed in order to maintain an adequate vitamin D status in 4-8 year-old Danish children during wintertime.

Detailed Description
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The main objective of ODIN Junior is to investigate whether and in which doses vitamin D intake is needed in order to maintain serum 25(OH)D concentrations above deficiency and insufficiency cut-offs (30 nmol/L and 50 nmol/L, respectively) in 4-8 year-old Danish children during the winter time. The children will be randomized to receive tablets with either 10 micrograms/day or 20 microgram/day of vitamin D3 (cholecalciferol), corresponding to one and two times the recommended daily intake in children, or placebo for 20 weeks. Measurements and blood sampling will be performed before the beginning and by the end of the intervention.

Official Title
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Food-based Solutions for Optimal Vitamin D Nutrition and Health Through the Life Cycle (ODIN) Junior

Conditions
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Vitamin D Deficiency

Intervention / Treatment
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* Dietary Supplement: Vitamin D3 (cholecalciferol)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 4-8 years at the start of the intervention healthy of white, Danish/European origin children must be Danish-speaking parents must read and speak Danish not planning a winter vacation south of a latitude of 51°North (corresponding to Surrey, England) Exclusion Criteria: diseases that may interfere with vitamin D or calcium metabolism intake of medication known to affect vitamin D or calcium metabolism use of vitamin D containing supplements ≥ 4 days/week the last 8 weeks before intervention start and use of any vitamin D containing supplements the last 4 weeks before intervention start concomitant participation in other studies involving dietary supplements or blood sampling serum calcium > 2.7 mmol/L at baseline

Ages Eligible for Study
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Minimum Age: 4 Years
Maximum Age: 8 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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Vitamin D (10 microgram/day)<br>Tablets with 10 microgram vitamin D3 (cholecalciferol) daily for 20 weeks. | Dietary Supplement: Vitamin D3 (cholecalciferol)<br> <br> |
| Experimental: Vitamin D (20 microgram/day)<br>Tablets with 20 microgram vitamin D3 (cholecalciferol) daily for 20 weeks. | Dietary Supplement: Vitamin D3 (cholecalciferol)<br> <br> |
| Placebo Comparator: Placebo control<br>Tablets with 0 microgram vitamin D daily for 20 weeks. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in vitamin D status | Serum concentrations of total 25-hydroxyvitamin D [25(OH)D] | Baseline and 20 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in anthropometric measurements | Waist circumference, body weight, height, body mass index (BMI) and BMI z-scores. | Baseline and 20 weeks | 
| Change in body composition | Fat mass, fat mass index (kg/m2), fat free mass and fat free mass index (kg/m2). | Baseline and 20 weeks | 
| Serum calcium | Serum calcium (adjusted for albumin) evaluated after the first visit has been completed for all children, and after the second visit. | Baseline and 20 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vitamin D, Children, Supplements, Cardiometabolic markers, Immune defense, Bone turnover, Muscle strength