Concentrations of 50 and 75 nmol/l are proposed as serum 25-hydroxyvitamin D (25(OH)D) target for older people from the view of bone health. We evaluated vitamin D status of elderly Finnish women in light of these definitions, its relationship to bone mineral density (BMD) and turnover, and improvement by summer sunshine.
Population-based study.
A total of 1604 ambulatory women aged 62-79 years were studied; 66% used vitamin D supplements. Serum 25(OH)D(3) was measured with HPLC before and after summer, and heel BMD in spring. In subgroups, serum parathyroid hormone (PTH) and type I procollagen aminoterminal propeptide (PINP) were analyzed.