Consequences of VD deficiency include rickets and osteomalacia. However, marginal concentrations of 25-hydroxyvitamin D (25(OH)VD) are associated with secondary hyperparathyroidism and osteoporosis. In this context, levels of 25(OH)VD capable to elevate parathyroid hormone (PTH) could be considered as insufficient. The VD insufficiency, although widely prevalent, is still under-recognized and under-treated. The authors have studied 180 patients followed in a endocrinology clinic in Belo Horizonte, who had 25(OH)VD measured, correlating it with PTH, biochemical bone turnover markers and bone mineral density. […]