Vitamin D Status and Seasonal Variation among Danish Children and Adults: A Descriptive Study.

The aim of the present study was to describe vitamin D status and seasonal variation in the general Danish population. In this study, 3092 persons aged 2 to 69 years (2565 adults, 527 children) had blood drawn twice (spring and autumn) between 2012 and 2014. A sub-sample of participants had blood samples taken monthly over a year.

Sun Exposure Guidelines and Serum Vitamin D Status in Denmark: The StatusD Study.

Little is known on how vitamin D status is affected by adherence to UVB-limiting sun exposure guidelines. Our aim was to investigate the relationship between adherence to the Danish sun exposure guidelines and vitamin D status. In total, 3194 Danes (2625 adults, 569 children) were recruited among the general population, and more than 92% had blood samples taken both autumn and spring.

Seasonal changes in vitamin D status among Danish adolescent girls and elderly women: the influence of sun exposure and vitamin D intake.

Background/objectives: To determine seasonal variation in vitamin D status in healthy Caucasian adolescent girls and elderly community-dwelling women living in Denmark, and to quantify the impact of sun exposure and intake on the seasonal changes in vitamin D status.

Subjects/methods: A 1-year longitudinal observational study of 54 girls (11-13 years) and 52 women (70-75 years). The participants were examined three times (winter-summer-winter).

Increased fracture risk in normocalcemic postmenopausal women with high parathyroid hormone levels: a 16-year follow-up study.

High PTH levels increase bone turnover and decrease bone mineral density (BMD). Low plasma 25-hydroxyvitamin D (25OHD) levels cause secondary hyperparathyroidism, but the relative contribution of low 25OHD and high PTH levels on risk of fracture is largely unknown. Within the cohort of women (n = 2,016) included in the Danish Osteoporosis Prevention Study (DOPS), we studied risk of fracture according to parathyroid status.