Sunlight Exposures Effect on Serum Vitamin D Levels

Vitamin D Deficiency Clinical Trial

Official title:

Sunlight Exposures Effect on Serum Vitamin D Levels

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00473317
• Other study ID #: Creighton3
• Status: Completed
• Phase: N/A
• First received: May 11, 2007
• Last updated: March 30, 2008
• Start date: July 2007
• Est. completion date: September 2007

Study information

• Verified date: March 2008
• Source: Creighton University
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

When people eat a meal, some, but not all of the calcium in that meal is absorbed, that is, moved into the bloodstream. When the skin is exposed to sunlight during summer months, Vitamin D is made there and then modified into more active forms by the liver and kidneys. These more active forms of Vitamin D improve calcium absorption. Many adults living in the U.S. have little or no sun exposure and are low in Vitamin D. We know that specific wavelengths of sunlight called Ultraviolet-B cause Vitamin D to be made in the skin.

Description:

At the beginning of the study we will measure your height, weight, skin color, and draw blood to measure your blood levels of Vitamin D and 25-hydroxyvitamin D. Each subject will wear a swimming suit and be exposed to sunlight for 30 minutes total (15 minutes lying on back, 15 minutes lying on stomach).We will draw blood for Vitamin D and 25-hydroxyvitamin D on days 1,2,3,5, and 7 after sunlight exposure. There will be six blood draws for a total of 102 cc of blood drawn (about 3 ½ teaspoons drawn each time).

Recruitment information / eligibility

• Status: Completed
• Enrollment: 6
• Est. completion date: September 2007
• Est. primary completion date: September 2007
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 19 Years to 50 Years

Eligibility

Inclusion Criteria:

• healthy males or females ages19-50 with "light" skin (self-assessed as Fitzpatrick skin type I-III) with minimal sun exposure and exogenous sources of vitamin D.

Exclusion Criteria:

• less than 16 oz milk per day, less than 10 hours of sun per week, no Vitamin D supplements, no anticonvulsants, no barbiturates, no steroids, no meds that increase photosensitivity, no granulomatous disease, no liver or kidney disease, no history of skin cancer, and BMI less than 30.

Study Design

Endpoint Classification: Pharmacodynamics Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Treatment

Related Conditions & MeSH terms

• Vitamin D Deficiency

Intervention

Behavioral:
• Sun Exposure
Each subject will wear a swimming suit and be exposed to sunlight for 30 minutes total (15 minutes lying on back, 15 minutes lying on stomach).

Locations

Country	Name	City	State
United States	Creighton University	Omaha	Nebraska

Sponsors (1)

Lead Sponsor	Collaborator
Creighton University

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	The goal of this study is to correlate vitamin D response and 25(OH)D response to sun exposure with most of the body (90 %) exposed to 0.25 hour of July sunlight at 41.2º N latitude and at approximately 1-2 pm in the afternoon.		1 week