Dietary Supplementation With 25-hydroxyvitamin D3 in Older Adults

Not Applicable

Completed

• Conditions: Vitamin D Status as Reflected by Serum 25-hydroxyvitamin D
• Interventions: Dietary Supplement: Placebo; Dietary Supplement: 25-hydroxyvitamin D3; Dietary Supplement: 25-hydroxyvitamin D (20 microgram/day); Dietary Supplement: vitamin D3

• Registration Number: NCT01398202
• Lead Sponsor: University College Cork

Brief Summary

The purpose of this study is to investigate whether a supplement of 25-hydroxyvitamin D is five-times more potent in raising vitamin D status (as reflected by serum 25(OH)D) compared to an equivalent amount of vitamin D3 in older adults. It will entail a 10 week supplementation study during winter months.

Detailed Description

The UK (McCance \& Widdowson) food composition tables suggests that 25-hydroxyvitamin D (which is present in some foods, albeit at very low concentrations, but which is also commercially available) may possess up to 5-times the activity of native vitamin D3 in food. Thus, in theory, each micogram of 25-hydroxyvitamin D consumed in the diet could boost vitamin D status up to five times most effectively compared to each microgram of native vitamin D in food. It is worth noting, however, that estimates of potency range from 2 to 5, depending on approach used, and that the real potency needs to be confirmed in a human study. This study aims to examine the biological activity of 25-hydroxyvitamin D (i.e., its potency relative to vitamin D3) as well as its effect on selected functional markers in a randomised, double-blind, human intervention trial in older adults.

Study Timeline

• Study Start: 2011-01
• Primary Completion: 2011-07
• Study First Submitted: 2011-07-18
• Study First Submitted QC: 2011-07-19
• Study First Posted: 2011-07-20
• Study Completion: 2011-09
• Status Verified: 2015-11
• Last Update Submitted: 2015-11-30
• Last Update Posted: 2015-12-02

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 56

Inclusion Criteria

• Subjects will be eligible if they are 45+ years of age
• Body Mass Index (BMI) 19-30

Exclusion Criteria

• have hypercalcaemia
• chronic illness
• renal or liver disorders
• taking medications that might interact with vitamin D or metabolite
• drank more than > 21 standards (male)/ 14 standards (female) of alcohol per week
• planning to change smoking habits

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	-
25-hydroxyvitamin D (7 microgram/day)	25-hydroxyvitamin D3	-
25-hydroxyvitamin D3 (20 micogram/day)	25-hydroxyvitamin D (20 microgram/day)	-
Vitamin D3 (20 microgram/day)	vitamin D3	-

Primary Outcome Measures

Name	Time	Method
serum 25-hydroxyvitamin D concentration	10 weeks

Secondary Outcome Measures

Name	Time	Method
biochemical markers of bone turnover	10 weeks
serum calcium adjusted for albumin	10 weeks
serum parathyroid hormone	10 weeks
blood pressure	10 weeks

Trial Locations

Locations (1)

University College Cork; 🇮🇪 Cork, Ireland