It appears you don't have support to open PDFs in this web browser. To view this file, Open with your PDF reader
Abstract
Humans obtain vitamin D from conversion of 7-dehydrocholesterol in the skin by ultraviolet B (UVB) radiation or from dietary sources. As the radiation level is insufficient in winter, vitamin D deficiency is common at higher latitudes. We assessed whether vernal solar UVB radiation at latitudes 61°N and 67°N in Finland has an impact on serum 25-hydroxyvitamin D [S-25(OH)D] concentrations. Twenty-seven healthy volunteers participated in outdoor activities in snow-covered terrain for 4–10 days in March or April, with their face and hands sun-exposed. The personal UVB doses and S-25(OH)D levels were monitored. A mean UVB dose of 11.8 standard erythema doses (SED) was received during an average of 12.3 outdoor hours. The mean S-25(OH)D concentration in subjects with a baseline concentration below 90.0 nmol/L (n=13) increased significantly, by 6.0 nmol/L from an initial mean of 62.4 nmol/L (p<0.001), whereas in those with a basal concentration above 90.0 nmol/L (n=12) it decreased significantly, by 6.7 nmol/L from a mean of 116.9 nmol/L (p<0.01). To conclude, only 7% of total body surface area was exposed to vernal sunlight and this was capable of increasing S-25(OH)D levels in subjects with a baseline level below 90 nmol/L but not in those with higher levels.
You have requested "on-the-fly" machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Show full disclaimer
Neither ProQuest nor its licensors make any representations or warranties with respect to the translations. The translations are automatically generated "AS IS" and "AS AVAILABLE" and are not retained in our systems. PROQUEST AND ITS LICENSORS SPECIFICALLY DISCLAIM ANY AND ALL EXPRESS OR IMPLIED WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES FOR AVAILABILITY, ACCURACY, TIMELINESS, COMPLETENESS, NON-INFRINGMENT, MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Your use of the translations is subject to all use restrictions contained in your Electronic Products License Agreement and by using the translation functionality you agree to forgo any and all claims against ProQuest or its licensors for your use of the translation functionality and any output derived there from. Hide full disclaimer
Details
1 Medical School, University of Tampere, Tampere, Finland; Department of Dermatology, Tampere University Hospital, Tampere, Finland; Department of Dermatology, Päijät-Häme Central Hospital, Lahti, Finland
2 Department of Dermatology, Tampere University Hospital, Tampere, Finland
3 Non ionizing radiation laboratory, Radiation and Nuclear Safety Authority, Helsinki, Finland
4 Unit of Primary Health Care, Helsinki University Central Hospital, Helsinki, Finland; Department of General Practice, University of Helsinki, Helsinki, Finland; Unit of Primary Health Care, Kuopio University Hospital, Helsinki and Kuopio, Finland
5 Finnish Meteorological Institute, Arctic Research Centre, Sodankylä, Finland
6 Aeronomy division, Sodankylä Geophysical Observatory, Sodankylä, Finland
7 Children’s Hospital, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland
8 Medical School, University of Tampere, Tampere, Finland
9 Medical School, University of Tampere, Tampere, Finland; Department of Dermatology, Tampere University Hospital, Tampere, Finland