Bioavailability of Vitamin D in Cod Liver Oil and Multivitamin Tablets in Healthy Subjects in Norway

Study Overview
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Brief Summary
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The main aim of the present study is to compare the bioavailability of vitamin D from cod liver oil and multivitamin tablets given to healthy individuals under the same conditions, as well as to study the influence of gender and ethnicity on vitamin D absorption. Healthy subjects will be randomised into two parallel groups receiving 10 micrograms (400 IU) per day of vitamin D3 from one fish oil capsule or one solid multivitamin tablet, respectively. Serum samples will be drawn at baseline and after four weeks (28 days) for the analysis of 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, parathyroid hormone, and tartrate resistant acid phosphatase in serum.

Official Title
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Bioavailability of Vitamin D in Cod Liver Oil and Multivitamin Tablets in Healthy Subjects in Norway

Conditions
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Healthy

Intervention / Treatment
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* Dietary Supplement: Fish oil capsule (specially manufactured for the study)
* Dietary Supplement: Multivitamin tablet of type: Vitaplex ABCD


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Must be able to meet at baseline and follow-up visit Exclusion Criteria: Using any vitamin D containing supplements regularly (> once per week) Travelled to sunny countries in the previous 3 months Used a tanning bed in the previous 3 months

Ages Eligible for Study
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Minimum Age: 18 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

Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Fish oil capsule<br> | Dietary Supplement: Fish oil capsule (specially manufactured for the study)<br>* One capsule per day for 4 weeks (28 days). The fish oil group receives a daily supplement of one fish oil capsule, specially manufactured for the present study by Peter Möller (now Möller's, Nydalen, Norway). The fish oil capsules are aimed to contain a dose of cholecalciferol identical to the dose already found in the multivitamin tablets by analysis in an independent laboratory (AS Vitas, Oslo, Norway), and similar doses of vitamin A. In addition, the fish oil capsule contains vitamin E and n-3 fatty acids.<br>|
| Experimental: Multivitamin tablet<br> | Dietary Supplement: Multivitamin tablet of type: Vitaplex ABCD<br>* One tablet per day for 4 weeks (28 days). The multivitamin group receives a daily supplement of one multivitamin tablet of type Vitaplex ABCD (Cederroth AS, Revetal, Norway), a common vitamin supplement sold in grocery stores in Norway. In addition to 10 micrograms (400 IU) of cholecalciferol,the multivitamin tablet contains vitamin A and the water-soluble vitamins: B1, B2, B6, Niacin, pantothenic acid, and vitamin C.<br>* Other names: Vitaplex ABCD;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in delta serum 25-hydroxyvitamin D (nmol/l) between the two parallel intervention groups |  | 4 weeks (28 days) between baseline and follow-up visit | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in delta 25-hydroxyvitamin D (nmol/l) between men and women |  | 4 weeks (28 days) between baseline and follow-up visit | 
| Difference in delta 25-hydroxyvitamin D (nmol/l) between ethnic groups |  | 4 weeks (28 days) between baseline and follow-up visit | 
| Correlation between change in 25-hydroxyvitamin D (nmol/l) and change in serum intact parathyroid hormone (pmol/l) |  | 4 weeks (28 days) between baseline and follow-up visit | 
| Correlation between change in 25-hydroxyvitamin D (nmol/l) and change in serum 1,25-dihydroxyvitamin D (pmol/l) |  | 4 weeks (28 days) between baseline and follow-up visit | 
| Correlation between change in 25-hydroxyvitamin D (nmol/l) and change in serum osteoclast-specific tartrate-resistant acid phosphatase (TRACP 5b); U/l |  | 4 weeks (28 days) between baseline and follow-up visit | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Bioavailability, Vitamin D metabolism, Bone turnover