Vitamin D Deficiency
Conditions
Keywords
Vitamin D deficiency, Sun, Genetics
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.
Interventions
None listed
Sponsors
Procter and Gamble
Creighton University
Study design
Observational model
COHORT
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* 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.
Exclusion criteria
* 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.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 25(OH)D levels | 1 month | 25(OH)D levels were measured at the only visit |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Genetic testing of 13 candidate genes | 1 month | 13 candidate genes were tested and their relationship to 25(OH)D examined. |
Countries
United States
Outcome results
None listed