The Role of Narrowband Ultraviolet B Exposure in the Maintenance of Vitamin D Levels During Winter

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT02275650

Enrollment

Registered

2014-10-27

Start date

2013-09-30

Completion date

2014-05-31

Last updated

2014-10-27

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

Conditions

Vitamin D Deficiency

Keywords

calcidiol, 25(oh)d, nbUVB, cyp27A1, cyp27B1, vitamin D

Brief summary

The investigators investigated the ability of narrowband ultraviolet B (nbUVB) treatment in the maintenance of vitamin D levels achieved during the summer in Finland. The investigators randomized 37 subjects into groups of 17 and 18 subjects. The other group received 2 standard erythema doses (SED) nbUVB exposure every other week until week 24, and serum 25(OH)D levels were measured at the onset and at weeks 6, 14, 20, 26 and 30. The control group was not illuminated and serum samples were analyzed correspondingly. Punch biopsies were taken at the onset and at week 14 for CYP27A1 and CYP27B1 enzyme expression level analyses.

Detailed description

The investigators investigated the ability of narrowband ultraviolet B (nbUVB) treatment in the maintenance of vitamin D levels achieved during the summer in Finland. The investigators randomized 37 subjects into groups of 17 and 18 subjects. The other group received 2 standard erythema doses (SED) nbUVB exposure every other week until week 24, and serum 25(OH)D levels were measured at the onset and at weeks 6, 14, 20, 26 and 30. The control group was not illuminated and serum samples were analyzed correspondingly. 6mm punch biopsies were taken at the onset and at week 14 for CYP27A1 and CYP27B1 enzyme expression level analyses.

Interventions

RADIATIONnbUVB

2 SED nbUVB exposure will be given every other week

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

PREVENTION

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Yes

Inclusion criteria

* age over 18 * Fitzpacker's skin type II-IV

Exclusion criteria

* age under 18 * diseases that inhibit vitamin D metabolism or absorption * Fitzpacker's skin type I * history of skin cancer * vitamin D substitution 1 month before baseline or during study * sun holidays 1 month before baseline or during study

Design outcomes

Primary

Measure	Time frame	Description
25(OH)D level	up to 30 weeks	Serum 25(OH)D levels were measured at the onset and at weeks 6, 14, 20, 26 and 30.

Secondary

Measure	Time frame	Description
CYP27A1 and CYP27B1 enzyme expression levels	up to 14 weeks	CYP27A1 and CYP27B1 enzyme expression levels will be analysed from 6mm punch biopsies at the onset and at week 14.

Countries

Finland

Outcome results

None listed

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