Public health implications of standardized 25-hydroxyvitamin D levels: A decrease in the prevalence of vitamin D deficiency among older women in Germany

► Estimates of vitamin D deficiency in Germany are much lower than previously thought. ► Two thirds of older (≥ 70 years) German women have 25(OH)D insufficiency (< 50 nmol/L). ► LC-MS/MS is essential for drawing public health implications of 25(OH)D deficiency. ► Determinants of 25(OH)D levels remain stable independent of season of blood draw.