Pilot Pharmacokinetic Study of Daily Versus Monthly High-Dose Cholecalciferol Supplementation
Condition: Healthy Volunteers
Study type: Interventional

Summary: 
      Research has shown that Vitamin D is important in preventing rickets in children,
      osteomalacia in adults, certain cancers, cardiovascular disease, Type 2 Diabetes, and
      metabolic syndrome. Data suggests that Vitamin D deficiency is common throughout the world.
      With increasing medical conditions being linked to Vitamin D deficiency, it is suggested that
      establishing early normal Vitamin D levels is important to long term health.

      There are low quantities of maternal Vitamin D that transfer from blood into breast milk.
      This places nursing infants at risk of developing low Vitamin D levels, and the American
      Academy of Pediatrics recommends they receive 400 international units (IU) of Vitamin D
      daily. If nursing mothers were supplemented with oral Vitamin D, this may produce adequate
      total Vitamin D in the breast milk for the growing infant to consume. By taking this
      potential therapeutic approach, this would prevent the burden of administering an oral
      Vitamin D liquid supplement to an infant.

      Recent laboratory technology now allows measurement of total Vitamin D (parent Vitamin D2
      plus parent Vitamin D3). The main objective of this pilot study is to compare total Vitamin D
      levels resulting from daily Vitamin D supplementation of 5,000 international units of
      cholecalciferol (Vitamin D3) orally for 28 days vs. 150,000 international units of
      cholecalciferol orally once in healthy, non-pregnant, non-lactating female subjects aged 18 �
      40. The research results will be used to help identify an optimal dosing regimen to
      administer to lactating mothers to hopefully deliver adequate total Vitamin D in nursing
      infants. This separate study will be conducted at a later date under a subsequent protocol.

      Previous research has demonstrated that Vitamin D3 levels become undetectable within 14 days
      after adult subjects received 100,000 international units of cholecalciferol. The
      investigators' central hypothesis is that daily dosing of 5,000 international units of
      cholecalciferol orally will maintain detectable total Vitamin D levels in serum after
      fourteen days, compared to high-dose 150,000 international units of oral cholecalciferol
      once.

      It is anticipated the aims of this pilot study will yield the following results. First, we,
      the investigators, hope to determine the resulting Vitamin D blood levels and calculate an
      appropriate dosing strategy for future research. Next we plan to measure the resulting
      25,hydroxyvitamin D levels that correspond with these dosing regimens, since
      25,hydroxyvitamin D is the major indicator of Vitamin D status in humans. Lastly, we will
      measure blood calcium and phosphorus levels to assure these doses of Vitamin D are tolerated
      by healthy female subjects.
    


Intervention name(s): Single High Dose Cholecalciferol; Daily Dose Cholecalciferol
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): Age 18 to 40 years, non-pregnant, non-lactating, female subjects will receive cholecalciferol 150,000 international units orally once (Bio-tech Pharmacal 50,000 IU capsule, Fayetteville, AR).; Age 18 to 40 years, non-pregnant, non-lactating, female subjects will receive cholecalciferol 5,000 IU capsule, Fayetteville, AR).
Other intervention name(s): Vitamin D3; Vitamin D3
Intervention MeSH terms: Vitamin D; Ergocalciferols; Cholecalciferol; Vitamins
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Basic Science
Keywords: healthy volunteers; healthy subjects; vitamin D; cholecalciferol; vitamin D3; total vitamin D