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The Effect of Weight on Vitamin D Dose Response (Weight)

This study has been completed.
Information provided by (Responsible Party):
Creighton University Identifier:
First received: November 12, 2009
Last updated: June 25, 2012
Last verified: June 2012
Vitamin D3 is a vitamin that is an essential component of biological regulating systems in humans. Sun exposure is the predominant source of vitamin D3. Previous research has shown that vitamin D3 deficiency is common worldwide. It is especially common in northern countries with long winters due to inadequate sun exposure during winter. In the US, an estimated 36% to 57% of healthy middle-aged to elderly adults have vitamin D3 deficiency. Current research indicates that obesity is associated with a low vitamin D3 level.

Condition Intervention
Obesity Vitamin D Deficiency Dietary Supplement: cholecalciferol

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Participant)
Primary Purpose: Treatment
Official Title: The Effect of Weight on Vitamin D Dose Response

Resource links provided by NLM:

Further study details as provided by Creighton University:

Primary Outcome Measures:
  • To characterize the dose response of 25(OH)D to 1,000, 5,000 or 10,000 IU/day of vitamin D3 for 21 weeks in a group of obese men and women. [ Time Frame: 21 weeks ]

Enrollment: 67
Study Start Date: November 2009
Study Completion Date: July 2011
Primary Completion Date: June 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: 1,000 IU
1,000 IU/day of vitamin D3
Dietary Supplement: cholecalciferol
daily dose
Active Comparator: 5,000 IU
5,000 IU/day of vitamin D3
Dietary Supplement: cholecalciferol
daily dose
Active Comparator: 10,000 IU
10,000 IU/day of vitamin D3
Dietary Supplement: cholecalciferol
daily dose

Detailed Description:
Obesity is a known risk factor for vitamin D deficiency. Adequate levels of vitamin D are important, not only for bone health, but appear to be important for prevention of certain autoimmune diseases, infections and cancers. Current FDA recommendations for vitamin D intake do not differentiate between lean and obese people. There are no published studies indicating if the 25(OH)D response to a given daily dose of vitamin D is any less in an obese person than a normal weight person. The purpose of this study is to characterize the quantitative relationship between steady state cholecalciferol input and the resulting serum 25 (OH)D concentration in obese subjects. Data obtained in this study will be compared to published normative data for non-obese subjects. Recommendations will be provided for optimal treatment of vitamin D deficiency in obese men and women.

Ages Eligible for Study:   19 Years to 60 Years   (Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • men aged 19 to 60 with BMI > 30.0.
  • They will have low (<1,000 IU) usual intake of vitamin D (from milk, multivitamins, supplements, and fortified foods)

Exclusion Criteria:

  • Subjects will not have history of hepatic or renal disease.
  • Subjects will not be taking medications known to affect vitamin D metabolism such as anti-seizure medications and/or corticosteroids.
  • They will not be on hydrochlorothiazide medications which could cause hypercalcemia.
  • They will not have diseases causing malabsorption of vitamin D, such as celiac sprue or small bowel surgeries.
  • Pregnancy is also an exclusion criterion.
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Please refer to this study by its identifier: NCT01013584

United States, Nebraska
Creighton University
Omaha, Nebraska, United States, 68131
Sponsors and Collaborators
Creighton University
Principal Investigator: Andjela Drincic, MD Creighton University
  More Information

Responsible Party: Creighton University Identifier: NCT01013584     History of Changes
Other Study ID Numbers: Creighton 8
Study First Received: November 12, 2009
Last Updated: June 25, 2012

Keywords provided by Creighton University:
vitamin D

Additional relevant MeSH terms:
Vitamin D Deficiency
Deficiency Diseases
Nutrition Disorders
Vitamin D
Growth Substances
Physiological Effects of Drugs
Bone Density Conservation Agents processed this record on September 20, 2017