Comparison of Changes in Serum 25(OH)D Concentrations Following Vitamin D Supplementation With Chewable Tablets Versus Pills

Study Overview
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Brief Summary
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This is a 6-month cross-over trial of vitamin D supplementation in 38 healthy men and women aged 18 years and older. The primary aim is to compare the change in serum 25(OH)D concentration following vitamin D supplementation with chewable tablets versus pills. Secondary aims are to evaluate satisfaction and adherence to the vitamin D chewable tablet supplement. Questionnaires on physical activity, sunlight exposure and dairy product consumption will be administered to adjust for confounding factors. A questionnaire will be administered to assess satisfaction and pill count to evaluate adherence to treatment. This research intends to test the hypothesis that the vitamin D chewable tablet supplement is as effective as a traditional vitamin D pill supplement to increase serum 25(OH)D concentrations.

Conditions
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Vitamin D Deficiency

Intervention / Treatment
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* Drug: Vitamin D chewable tablet supplementation
* Drug: Vitamin D pill supplementation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Caucasian men and women; Aged 18 years and older; Having a serum 25(OH)D concentration of 75 nmol/L or less. Exclusion Criteria: Regular consumption of a supplement containing > 400 IU/d of vitamin D over the last 2 months; Intestinal malabsorption; Cirrhosis; Renal insufficiency (creatinine clearance <60 ml/min); Hypercalcemia; Pregnancy; Breastfeeding; Inability to provide informed consent.

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

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: wash-out<br>2 months | |
| Experimental: Vitamin D chewable tablet supplementation<br>A chewable vitamin D tablet containing 1000 IU to be taken once a day for 2 months. | Drug: Vitamin D chewable tablet supplementation<br> <br> |
| Experimental: Vitamin D pill supplementation<br>A vitamin D pill containing 1000 IU to be taken once a day for 2 months. | Drug: Vitamin D pill supplementation<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Serum 25(OH)D concentration |  | 0 and 2 months, 4 and 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Satisfaction with the vitamin D chewable tablets and pills. | Satisfaction will be assessed using a questionnaire administered by the research team. | 0 and 2 months, 4 and 6 months | 
| Adherence to the vitamin D chewable tablets and pills. | This issue will be assessed by pill count. | 0 and 2 months, 4 and 6 months |