Vitamin-D Insufficiency Clinical Trial
Official title:
Seasonal Variations in Serum 25-hydroxy Vitamin-D Levels in a Swedish Cohort
The purpose of this study was to study seasonal inter-individual and intra-individual variations in S-25(OH)D and to explore parameters associated with S-25-OHD in healthy Swedish adults.
Serum was collected during 12 months and analysed for 25(OH)D in 540 healthy blood donors. The blood donors answered questionnaires concerning vitamin D supplements, smoking, physical activity, sunbed use and holidays in sunny locations. Repeated serum samples were also collected from thrombocyte donors to study the intra-individual variations in S-25(OH)D. ;
Observational Model: Cohort, Time Perspective: Cross-Sectional