Environmental & Genetic Influences on Vitamin D Status
- Conditions
- Vitamin D Deficiency
- Registration Number
- NCT01208636
- Lead Sponsor
- Creighton University
- Brief Summary
The purpose of this study is to determine the effect of environmental and genetic influences on Vitamin D status.
- Detailed Description
Vitamin D deficiency is a common problem. The principal source of vitamin D for humans is solar exposure, with cutaneous synthesis of vitamin D by photoconversion of 7-dehydrocholesterol in the skin to pre-vitamin D3. Latitude, altitude, season, skin pigmentation, and age are recognized factors that influence how much vitamin D can be made by solar exposure. Surprisingly, Vitamin D deficiency has been described in people dwelling in southern Florida and in surfers in Hawaii. We hypothesize that genetic variations in vitamin metabolism accounts for these differences.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 40
- Able to consent and come for a study visit.
- Male or female between ages 18-60.
- Sun exposure >3 hours daily for at least 5 days weekly for the last 3 months.
- Unable to consent or come to a visit
- Taking Vitamin D supplements, anticonvulsants, barbiturates, steroids, having granulomatous disease, or liver or kidney disease as these medications and conditions interfere with Vitamin D metabolism.
- Related to another participant by blood.
Study & Design
- Study Type
- OBSERVATIONAL
- Study Design
- Not specified
- Primary Outcome Measures
Name Time Method 25(OH)D levels 1 month 25(OH)D levels were measured at the only visit
- Secondary Outcome Measures
Name Time Method Genetic testing of 13 candidate genes 1 month 13 candidate genes were tested and their relationship to 25(OH)D examined.
Trial Locations
- Locations (1)
Creighton University
🇺🇸Omaha, Nebraska, United States