The Relation Between Vitamin D Production and UVB Exposed Body Surface Area

Interdependence Between Body Surface Area and UVB Dose in Vitamin D Production: A Randomized Controlled Trial

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT01042197

Enrollment

Registered

2010-01-05

Start date

2008-01-31

Completion date

2009-12-31

Last updated

2010-01-12

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Vitamin D Status

Keywords

Vitamin D, UVB, Dose-Response, Body surface area

Brief summary

The purpose of this study is to investigate the relation between vitamin D production after UVB and exposed body surface areas with different UVB doses.

Detailed description

Vitamin D deficiency is very common. Rachitis, osteoporosis, cancer, sclerosis as well as cardiovascular diseases are related to vitamin D deficiency. Elderly people, immigrants as well as patients with malabsorption diseases often have vitamin D deficiency. 90-95 % of the total vitamin D requirements are obtained from the ultraviolet (UV) radiation of the skin.In spite of the risk of skin-cancer, treatment with sunlight radiation is often recommended against vitamin D deficiency. This fact has raised a scientific debate, where concern has been expressed with regard to the risk of skin-cancer. This dilemma should also be examined as no human studies are available on the vitamin D production in the skin after UV-radiation showing the frequency and dose necessary for sufficient production of vitamin D. The lowest exposure frequency, the smallest body surface area and the lowest UV dose should therefore be established to be exposed in order to minimize the risk of skin-cancer by unnecessary UV-radiation. The purpose of the project is therefore to clarify which factors there are of importance for the production of vitamin D in the skin after UVB radiation.

Interventions

RADIATIONBroadband UVB

UVB dose: 0.75 SED. Four UVB sessions with 2 days in between.

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

BASIC_SCIENCE

Masking

DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender

ALL

Age

18 Years to 65 Years

Healthy volunteers

Yes

Inclusion criteria

* Healthy individuals between 18 - 65 years of age. * Avoidance of sun bed exposure * Not Holidaying south of 45 degrees latitude 3 months before * Avoiding vitamin D supplementation during and two months before

Exclusion criteria

* Illness as well as age above 65 years. * Skin diseases * Psychiatric diseases * Drug addiction * Intake of photosensitive medicine. * Intake of cholesterol-lowering medicine. * Pregnancy

Design outcomes

Primary

Measure	Time frame
Vitamin D (nmol/l) measured in a blood sample to define just how much sun exposure is necessary to obtain a sufficient vitamin D production.	Before and 2 days after the last UVB session.

Countries

Denmark

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026