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Inter-relationship Between Vitamin D Requirements and Calcium Intake in Older Adults (VitD-Ca)

Primary Purpose

Vitamin D Deficiency

Status
Completed
Phase
Not Applicable
Locations
Ireland
Study Type
Interventional
Intervention
Vitamin D3 (20 micrograms/day)
Placebo
Sponsored by
University College Cork
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional prevention trial for Vitamin D Deficiency focused on measuring Vitamin D status, 25-hydroxyvitamin D, Vitamin D3, RCT, Calcium intake, Dietary requirement

Eligibility Criteria

50 Years - 80 Years (Adult, Older Adult)All SexesAccepts Healthy Volunteers

Inclusion Criteria:

Consenting white men and women aged ≥ 50 y

Exclusion Criteria:

  • Unwilling to discontinue consumption of vitamin D-containing supplements 4 wks before the initiation of the study and throughout the study.
  • Planning to take a winter vacation (during the course of the 15-wk intervention) to a location at which either the altitude or the latitude was predicted to result in significant cutaneous vitamin D synthesis from solar radiation (e.g., a winter sun coastal resort or a mountain ski resort)
  • Use of tanning facilities of any type.
  • Pregnancy or planning to become pregnant during the study
  • A severe medical illness,
  • hypercalcaemia,
  • Known intestinal malabsorption syndrome,
  • Excessive alcohol use,
  • Taking medications known to interfere with vitamin D metabolism

Sites / Locations

  • Human Dietary Studies Facility, School of Food and Nutritional Sciences, University College Cork, Cork, Ireland

Arms of the Study

Arm 1

Arm 2

Arm 3

Arm 4

Arm Type

Placebo Comparator

Active Comparator

Placebo Comparator

Active Comparator

Arm Label

Placebo in high calcium group

Vitamin D3 in low/moderate calcium group

Placebo in low/moderate calcium group

Vitamin D3 in high calcium group

Arm Description

Placebo + habitual dietary calcium intake (>1000 mg/d)

Vitamin D3 (20 microgram/day) + habitual calcium intake <700 mg/d

Placebo + habitual calcium intake <700 mg/d

Vitamin D3 (20 microgram/day) + habitual calcium intake (>1000 mg/d)

Outcomes

Primary Outcome Measures

Response of serum 25(OH)D concentration over winter in subjects stratified by calcium intake

Secondary Outcome Measures

Serum albumin-adjusted calcium
serum parathyroid hormone
Serum 24,25(OH)2D
Serum 1,25(OH)2D
Serum free 25(OH)D
Serum vitamin D binding protein

Full Information

First Posted
November 8, 2013
Last Updated
November 21, 2013
Sponsor
University College Cork
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1. Study Identification

Unique Protocol Identification Number
NCT01990872
Brief Title
Inter-relationship Between Vitamin D Requirements and Calcium Intake in Older Adults
Acronym
VitD-Ca
Official Title
Randomized Controlled Trial to Explore the Inter-relationship Between Vitamin D Requirements and Calcium Intake
Study Type
Interventional

2. Study Status

Record Verification Date
November 2013
Overall Recruitment Status
Completed
Study Start Date
October 2012 (undefined)
Primary Completion Date
November 2013 (Actual)
Study Completion Date
November 2013 (Actual)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Principal Investigator
Name of the Sponsor
University College Cork

4. Oversight

Data Monitoring Committee
Yes

5. Study Description

Brief Summary
This winter-based placebo-controlled, single-dose vitamin D randomized controlled trial (RCT) aims to examine the impact of various levels of habitual calcium intake on dietary vitamin D requirements in older adults stratified by calcium intake. This will provide new data on the impact of different levels of calcium intake, ranging from low/moderate to high, on winter serum 25(OH)D levels, and their utilization and catabolism in adults.
Detailed Description
The aim of this study is to perform a randomised controlled vitamin D3 intervention study in apparently healthy, free-living adults (aged 50+ y) to investigate whether different levels of habitual calcium intake, ranging from low-moderate to high, influence serum 25(OH)D concentrations and indices of vitamin D activation and catabolism during winter, when vitamin D intake is adequate versus inadequate. This research will provide new data and scientific understanding in relation to the impact of different levels of dietary calcium intake on vitamin D requirements in the older adult population. As such, this new data will inform dietary reference values for vitamin D.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Vitamin D Deficiency
Keywords
Vitamin D status, 25-hydroxyvitamin D, Vitamin D3, RCT, Calcium intake, Dietary requirement

7. Study Design

Primary Purpose
Prevention
Study Phase
Not Applicable
Interventional Study Model
Parallel Assignment
Masking
ParticipantInvestigator
Allocation
Randomized
Enrollment
125 (Actual)

8. Arms, Groups, and Interventions

Arm Title
Placebo in high calcium group
Arm Type
Placebo Comparator
Arm Description
Placebo + habitual dietary calcium intake (>1000 mg/d)
Arm Title
Vitamin D3 in low/moderate calcium group
Arm Type
Active Comparator
Arm Description
Vitamin D3 (20 microgram/day) + habitual calcium intake <700 mg/d
Arm Title
Placebo in low/moderate calcium group
Arm Type
Placebo Comparator
Arm Description
Placebo + habitual calcium intake <700 mg/d
Arm Title
Vitamin D3 in high calcium group
Arm Type
Active Comparator
Arm Description
Vitamin D3 (20 microgram/day) + habitual calcium intake (>1000 mg/d)
Intervention Type
Dietary Supplement
Intervention Name(s)
Vitamin D3 (20 micrograms/day)
Intervention Description
Vitamin D3 (20 micrograms/day)
Intervention Type
Dietary Supplement
Intervention Name(s)
Placebo
Intervention Description
Placebo (0 micrograms vitamin D3/day)
Primary Outcome Measure Information:
Title
Response of serum 25(OH)D concentration over winter in subjects stratified by calcium intake
Time Frame
0, 8, 15 weeks
Secondary Outcome Measure Information:
Title
Serum albumin-adjusted calcium
Time Frame
0, 8, 15 weeks
Title
serum parathyroid hormone
Time Frame
0, 8, 15 weeks
Title
Serum 24,25(OH)2D
Time Frame
0 and 15 weeks
Title
Serum 1,25(OH)2D
Time Frame
0 and 15 weeks
Title
Serum free 25(OH)D
Time Frame
0 and 15 weeks
Title
Serum vitamin D binding protein
Time Frame
0 and 15 weeks

10. Eligibility

Sex
All
Minimum Age & Unit of Time
50 Years
Maximum Age & Unit of Time
80 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
Inclusion Criteria: Consenting white men and women aged ≥ 50 y Exclusion Criteria: Unwilling to discontinue consumption of vitamin D-containing supplements 4 wks before the initiation of the study and throughout the study. Planning to take a winter vacation (during the course of the 15-wk intervention) to a location at which either the altitude or the latitude was predicted to result in significant cutaneous vitamin D synthesis from solar radiation (e.g., a winter sun coastal resort or a mountain ski resort) Use of tanning facilities of any type. Pregnancy or planning to become pregnant during the study A severe medical illness, hypercalcaemia, Known intestinal malabsorption syndrome, Excessive alcohol use, Taking medications known to interfere with vitamin D metabolism
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Kevin D Cashman, BSc. PhD
Organizational Affiliation
University College Cork
Official's Role
Principal Investigator
Facility Information:
Facility Name
Human Dietary Studies Facility, School of Food and Nutritional Sciences, University College Cork, Cork, Ireland
City
Cork
Country
Ireland

12. IPD Sharing Statement

Citations:
PubMed Identifier
24828024
Citation
Cashman KD, Kinsella M, Walton J, Flynn A, Hayes A, Lucey AJ, Seamans KM, Kiely M. The 3 epimer of 25-hydroxycholecalciferol is present in the circulation of the majority of adults in a nationally representative sample and has endogenous origins. J Nutr. 2014 Jul;144(7):1050-7. doi: 10.3945/jn.114.192419. Epub 2014 May 14.
Results Reference
derived
PubMed Identifier
24695896
Citation
Cashman KD, Hayes A, O'Donovan SM, Zhang JY, Kinsella M, Galvin K, Kiely M, Seamans KM. Dietary calcium does not interact with vitamin D(3) in terms of determining the response and catabolism of serum 25-hydroxyvitamin D during winter in older adults. Am J Clin Nutr. 2014 Jun;99(6):1414-23. doi: 10.3945/ajcn.113.080358. Epub 2014 Apr 2.
Results Reference
derived

Learn more about this trial

Inter-relationship Between Vitamin D Requirements and Calcium Intake in Older Adults

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