title: Vitamin D status and its adequacy in healthy Danish perimenopausal women: relationships to dietary intake, sun exposure and serum parathyroid hormone.
abstract: We conducted this study to assess the prevalence of vitamin D insufficiency in a population of normal perimenopausal women, to examine the influence of sun exposure and vitamin D intake on the concentration of 25-hydroxyvitamin D (25OHD) and to examine the association between parathyroid hormone (PTH) and 25OHD. A total of 2016 healthy women aged 45-58, who had recently undergone a natural menopause, were enrolled over a 2.5-year period in the Danish Osteoporosis Prevention Study. A marked seasonal fluctuation of 25OHD was seen, with an abrupt rise in June and high values until October. The fluctuation could be related to number of hours of sunshine per month with a two months time lag. Dietary vitamin D intake, vitamin supplementation, sunlight exposure, and use of sun-bed were all significantly related to 25OHD concentrations. Sun exposure seemed to contribute the most. The overall prevalence of vitamin D deficiency (defined as serum ) was 7 %. However, in the subgroup avoiding direct sunshine and abstaining from vitamin D supplementation 32.8 % were vitamin D deficient in the winter-spring period. Although mean PTH was increased in the group with low serum 25OHD, PTH was not a sensitive marker of hypovitaminosis D in the individual, as only 16 % of those with vitamin D deficiency had PTH levels above normal range. Thus, we have shown, that healthy middle-aged Danish women are prone to vitamin D insufficiency in the winter-spring period, if they avoid sun exposure in the summer period and abstain from vitamin D supplementation.
authors.affiliation: Osteoporosis Research Clinic, Dep 545, Copenhagen University Hospital Hvidovre, Kettegaard Allé 30, DK- 2650 Hvidovre, Denmark. cxb@fdir.dk
authors.forename: C
authors.initials: C
authors.lastname: Brot
authors.forename: P
authors.initials: P
authors.lastname: Vestergaard
authors.forename: N
authors.initials: N
authors.lastname: Kolthoff
authors.forename: J
authors.initials: J
authors.lastname: Gram
authors.forename: A P
authors.initials: AP
authors.lastname: Hermann
authors.forename: O H
authors.initials: OH
authors.lastname: Sørensen
mesh_terms: D015415:Biomarkers / Q000097:blood; D002112:Calcifediol / Q000097:blood*; D003718:Denmark; D004032:Diet; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D007044:Hysterectomy; D016014:Linear Models; D008593:Menopause / Q000097:blood*; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D015995:Prevalence; D012044:Regression Analysis; D014466:Ultraviolet Rays; D014807:Vitamin D / Q000008:administration & dosage*; D014808:Vitamin D Deficiency / Q000453:epidemiology* / Q000517:prevention & control
chemical_list: D015415:Biomarkers; D010281:Parathyroid Hormone; D014807:Vitamin D; D005640:Follicle Stimulating Hormone; D002112:Calcifediol