Relative Efficacy of Vitamins D2 and D3 in Adult Humans


Vitamin D2 in chronic dosing will produce less of an elevation of serum 25(OH)D than will the same dose of vitamin D3.

Full Title of Study: “Vitamin D Status: Relative Efficacy of Vitamins D2 and D3”

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: Randomized
    • Intervention Model: Parallel Assignment
    • Primary Purpose: Prevention
    • Masking: Single (Outcomes Assessor)
  • Study Primary Completion Date: August 2010


  • Dietary Supplement: vitamin D2
    • Study Supplement
  • Dietary Supplement: vitamin D3
    • Study Supplement

Arms, Groups and Cohorts

  • Active Comparator: vitamin D2
  • Active Comparator: vitamin D3

Clinical Trial Outcome Measures

Primary Measures

  • AUC for increment in serum 25(OH)D
    • Time Frame: 12 weeks

Secondary Measures

  • change in vitamin D content of subcutaneous fat
    • Time Frame: 12 weeks

Participating in This Clinical Trial

Inclusion Criteria

  • willingness to withhold supplement use for duration of study – willingness to avoid sun exposure for duration of study Exclusion Criteria:

  • vitamin D supplement use – conditions that affect vitamin D metabolism by the body

Gender Eligibility: All

Minimum Age: 21 Years

Maximum Age: 65 Years

Are Healthy Volunteers Accepted: Accepts Healthy Volunteers

Investigator Details

  • Lead Sponsor
    • Creighton University
  • Collaborator
    • Health Future Foundation
  • Provider of Information About this Clinical Study
    • Sponsor
  • Overall Official(s)
    • Robert P Heaney, MD, Principal Investigator, Creighton University

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