Working…
COVID-19 is an emerging, rapidly evolving situation.
Get the latest public health information from CDC: https://www.coronavirus.gov.

Get the latest research information from NIH: https://www.nih.gov/coronavirus.
ClinicalTrials.gov
ClinicalTrials.gov Menu

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

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
 
ClinicalTrials.gov Identifier: NCT01990872
Recruitment Status : Completed
First Posted : November 25, 2013
Last Update Posted : November 25, 2013
Sponsor:
Information provided by (Responsible Party):
Kevin D. Cashman, University College Cork

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.

Condition or disease Intervention/treatment Phase
Vitamin D Deficiency Dietary Supplement: Vitamin D3 (20 micrograms/day) Dietary Supplement: Placebo Not Applicable

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.

Layout table for study information
Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 125 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Prevention
Official Title: Randomized Controlled Trial to Explore the Inter-relationship Between Vitamin D Requirements and Calcium Intake
Study Start Date : October 2012
Actual Primary Completion Date : November 2013
Actual Study Completion Date : November 2013

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Calcium Vitamin D

Arm Intervention/treatment
Placebo Comparator: Placebo in high calcium group
Placebo + habitual dietary calcium intake (>1000 mg/d)
Dietary Supplement: Placebo
Placebo (0 micrograms vitamin D3/day)

Active Comparator: Vitamin D3 in low/moderate calcium group
Vitamin D3 (20 microgram/day) + habitual calcium intake <700 mg/d
Dietary Supplement: Vitamin D3 (20 micrograms/day)
Vitamin D3 (20 micrograms/day)

Placebo Comparator: Placebo in low/moderate calcium group
Placebo + habitual calcium intake <700 mg/d
Dietary Supplement: Placebo
Placebo (0 micrograms vitamin D3/day)

Active Comparator: Vitamin D3 in high calcium group
Vitamin D3 (20 microgram/day) + habitual calcium intake (>1000 mg/d)
Dietary Supplement: Vitamin D3 (20 micrograms/day)
Vitamin D3 (20 micrograms/day)




Primary Outcome Measures :
  1. Response of serum 25(OH)D concentration over winter in subjects stratified by calcium intake [ Time Frame: 0, 8, 15 weeks ]

Secondary Outcome Measures :
  1. Serum albumin-adjusted calcium [ Time Frame: 0, 8, 15 weeks ]
  2. serum parathyroid hormone [ Time Frame: 0, 8, 15 weeks ]
  3. Serum 24,25(OH)2D [ Time Frame: 0 and 15 weeks ]
  4. Serum 1,25(OH)2D [ Time Frame: 0 and 15 weeks ]
  5. Serum free 25(OH)D [ Time Frame: 0 and 15 weeks ]
  6. Serum vitamin D binding protein [ Time Frame: 0 and 15 weeks ]


Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.


Layout table for eligibility information
Ages Eligible for Study:   50 Years to 80 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
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

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01990872


Locations
Layout table for location information
Ireland
Human Dietary Studies Facility, School of Food and Nutritional Sciences, University College Cork, Cork, Ireland
Cork, Ireland
Sponsors and Collaborators
University College Cork
Investigators
Layout table for investigator information
Principal Investigator: Kevin D Cashman, BSc. PhD University College Cork
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Layout table for additonal information
Responsible Party: Kevin D. Cashman, Professor of Food and Health, University College Cork
ClinicalTrials.gov Identifier: NCT01990872    
Other Study ID Numbers: PR-IC-1111-10005
First Posted: November 25, 2013    Key Record Dates
Last Update Posted: November 25, 2013
Last Verified: November 2013
Keywords provided by Kevin D. Cashman, University College Cork:
Vitamin D status
25-hydroxyvitamin D
Vitamin D3
RCT
Calcium intake
Dietary requirement
Additional relevant MeSH terms:
Layout table for MeSH terms
Vitamin D Deficiency
Avitaminosis
Deficiency Diseases
Malnutrition
Nutrition Disorders
Vitamin D
Cholecalciferol
Vitamins
Micronutrients
Nutrients
Growth Substances
Physiological Effects of Drugs
Bone Density Conservation Agents
Calcium-Regulating Hormones and Agents