A Single Wintertime Dose of Vitamin D3 to Prevent Winter Decline in Vitamin D Status in Healthy Adults

July 11, 2017 updated by: Vin Tangpricha, MD, PH.D, Emory University

A Single Wintertime Dose of Vitamin D3 to Prevent Winter Decline in Vitamin D Concentrations in Healthy Adults: A Pilot Study

The purpose of this study is to determine if a single dose of vitamin D administered orally in the fall will provide adequate vitamin D in healthy individuals for the duration of the winter, during which vitamin D levels are known to decrease. The investigators are also interested in finding out if this level of vitamin D will provide adequate levels for the remainder of the year. While the benefits of once-yearly vitamin D administration are clear for patients with osteoporosis, osteomalacia, rickets, and other conditions associated with vitamin D deficiency and high bone turn-over, studies have not been performed in which high doses of vitamin D were used to prevent the seasonal decline of vitamin D concentrations in healthy individuals. These findings could provide evidence to support vitamin D administration to healthy individuals in the wintertime to improve health outcomes, and provide the basis for additional studies in both healthy and sick populations.

Study Overview

Detailed Description

Vitamin D, synthesized from 7-dehydrocholesterol during ultraviolet- B exposure, aids in the absorption of calcium from the G.I. tract. Indirectly, by maintaining optimal calcium homeostasis, adequate vitamin D concentrations are essential in skeletal health (by preventing rickets and osteomalacia), cardiovascular health (by lowering the risk for hypertension), and ultimately decreasing mortality. Due to decreased direct sunlight exposures in the winter (characterized by limited outdoor activity, increased clothing coverage, and angle of the sun), vitamin D concentrations are shown to decline in individuals over the winter. Once-yearly administration of a bolus of vitamin D offers a means of preventing the seasonal decline in vitamin D status and preventing vitamin D deficiency. If proven successful, a once-yearly dose of vitamin D would provide improved compliance relative to daily or monthly dosing and provide an inexpensive and easy way to ensure optimal concentrations of vitamin D year-round.

This pilot study plans to investigate if once a year dosing with vitamin D during the winter months in self-identified healthy adults will be effective in maintaining optimal vitamin D status for the entire year. In brief, this study will be a randomized, double blind, placebo-controlled study to evaluate the efficacy of 250,000 IU of vitamin D3 compared to placebo given once in 30 healthy individuals (15 subjects per arm) in November. The serum 25(OH)D (the best measurable level of vitamin D status) will be measured after both 3-4 months and 1 year to determine the efficacy of the dose relative to the 15 healthy controls. The intent of this clinical investigation is not to evaluate the dietary supplement's ability to diagnose, cure, mitigate or prevent disease. This study is to evaluate blood concentrations of this regimen of vitamin D.

Ultimately, this study hopes to determine if a single dose of vitamin D administered orally in the fall will provide adequate vitamin D in healthy young individuals for the 3 months during winter, during which vitamin D levels are known to decrease, and over the entire year. These findings could provide evidence to support vitamin D administration to healthy individuals in wintertime to improve health outcomes, and provide the basis for additional studies in both healthy and sick populations.

Secondary outcomes of this study will evaluate other hypothesized effects of vitamin D on biomarkers affecting health status and immunity, including markers of inflammation and markers of iron status.

Study Type

Interventional

Enrollment (Actual)

28

Phase

  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Georgia
      • Atlanta, Georgia, United States, 30322
        • Emory University Campus

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 65 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

1. Healthy adult (by self-report) between ages 18-65

Exclusion Criteria:

  1. reported granulomatous conditions
  2. history of kidney disease (renal failure, renal stones, serum creatinine over 0.06 ng/mL in the past)
  3. diabetes
  4. currently taking anticonvulsants, barbituates, antihypertensives, steroids of any form, or drugs that effect bone metabolism
  5. history of calcium or bone abnormalities (including osteoporosis)
  6. primary hyperparathyroidism
  7. thyrotoxicosis
  8. Paget's disease
  9. history of malignancy
  10. known liver disease
  11. calcium supplements >1000 mg/day
  12. complete immobilization

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Placebo Comparator: Placebo Pill
Received identical pills that do not contain vitamin D. Blood levels of 25(OH)D determined at 10 days, 3 months, and 1 year following placebo dose.
Active Comparator: Vitamin D
250,000 IU cholecalciferol as single, oral dose. Blood levels 25(OH)D measured at 10 days, 3 months, and 1 year following dose.
250,000 IU cholecalciferol (vitamin D3) provided as a single oral dose.
Other Names:
  • vitamin D3

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
blood levels of 25(OH)D
Time Frame: 3 months
Measure blood levels of 25(OH)D, an indicator of vitamin D status, at 10 days, 3 months, and 1 year following vitamin D or placebo dose.
3 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Blood Calcium level
Time Frame: 10 days
Measured blood calcium levels at 10 days following dose. This measure assessed safety of large vitamin D dose regarding its potential to cause hypercalcemia.
10 days
Blood pro-inflammatory cytokines
Time Frame: baseline, 10 days, 3 months, 1 year
Measured blood cytokine (IL-6, IL-1B, IL-8, MCP-1) concentrations at baseline, 10 days, 3 months, and 1 year
baseline, 10 days, 3 months, 1 year
Blood hepcidin concentration
Time Frame: baseline, 10 days
Measured blood hepcidin concentrations at baseline and 10 days
baseline, 10 days
Blood markers of iron status
Time Frame: baseline, 10 days
Measured blood ferritin concentrations at baseline and 10 days
baseline, 10 days

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Vin Tangpricha, MD, PhD, Emory University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

October 1, 2012

Primary Completion (Actual)

December 1, 2013

Study Completion (Actual)

July 1, 2017

Study Registration Dates

First Submitted

August 12, 2013

First Submitted That Met QC Criteria

August 16, 2013

First Posted (Estimate)

August 19, 2013

Study Record Updates

Last Update Posted (Actual)

July 13, 2017

Last Update Submitted That Met QC Criteria

July 11, 2017

Last Verified

July 1, 2017

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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