Funding sources This study was supported by National Graduate School of Clinical Investigation (M.A.-H.), Finnish Dermatological Society (M.A.-H.) and Competitive Research Funding of the Tampere University Hospital (Grants 9J103 and 9K104).
Comparison of narrowband ultraviolet B exposure and oral vitamin D substitution on serum 25-hydroxyvitamin D concentration
Article first published online: 28 JUN 2012
© 2012 The Authors. BJD © 2012 British Association of Dermatologists
British Journal of Dermatology
Volume 167, Issue 1, pages 160–164, July 2012
How to Cite
Ala-Houhala, M.J., Vähävihu, K., Hasan, T., Kautiainen, H., Ylianttila, L., Viljakainen, H.T., Snellman, E. and Reunala, T. (2012), Comparison of narrowband ultraviolet B exposure and oral vitamin D substitution on serum 25-hydroxyvitamin D concentration. British Journal of Dermatology, 167: 160–164. doi: 10.1111/j.1365-2133.2012.10990.x
Conflicts of interest None declared.
- Issue published online: 28 JUN 2012
- Article first published online: 28 JUN 2012
- Accepted manuscript online: 18 APR 2012 01:28PM EST
- Accepted for publication 3 April 2012
Summary Background A short course of narrowband ultraviolet B (NB-UVB) exposures increases the serum 25-hydroxyvitamin D [25(OH)D] concentration in patients with psoriasis and healthy subjects.
Objectives To compare the effects of NB-UVB and oral vitamin D substitution in healthy subjects in winter.
Methods Healthy adult hospital employees and medical students were screened for serum 25(OH)D concentration. Those with 25(OH)D below 75 nmol L−1 were randomly given either 12 NB-UVB exposures or 20 μg of oral cholecalciferol daily for 4 weeks. The NB-UVB exposures were given with a Waldmann UV 7001 cabin and the mean cumulative dose was 48·4 standard erythema doses. Serum 25(OH)D was measured before and after the treatments by radioimmunoassay.
Results The baseline serum 25(OH)D concentrations were 52·9 ± 10·4 (mean ± SD) in the 33 NB-UVB-treated and 53·5 ± 12·7 nmol L−1 in the 30 oral cholecalciferol-treated subjects. The mean increase in serum 25(OH)D was 41·0 nmol L−1 [95% confidence interval (CI) 34·8–47·2; P < 0·001] in the NB-UVB group and 20·2 nmol L−1 (95% CI 14·6–26·0; P < 0·001) in the cholecalciferol group. The difference between the two treatments was significant at 2 weeks (P = 0·033) and at 4 weeks (P < 0·001). One month after the treatments the 25(OH)D concentrations had increased further.
Conclusions The present study shows that 12 NB-UVB exposures given during 4 weeks increase serum 25(OH)D concentration significantly more than 20 μg of oral cholecalciferol daily. A short NB-UVB course is an effective way to improve vitamin D balance in winter and the response is still evident 2 months after the course.