In the last 20-30 years, increasing awareness of the role of vitamin D in the pathogenesis of some musculoskeletal and extra-skeletal diseases, together with substantial epidemiologic evidence on the prevalence of hypovitaminosis D in the general adult population and in the elderly, have given rise to an ever-growing debate concerning the appropriateness of the strategies for the prevention and treatment of vitamin D deficiency.
A number of scientific works have investigated the use of cholecalciferol and vitamin D metabolites (calcifediol in particular) for the prevention and treatment of vitamin D deficiency. Undoubtedly, the great number of these randomized, controlled trials (RCTs) have produced a significant advance in our knowledge on this topic, highlighting extremely important clinical aspects. However, the quantity, quality (not always high) and heterogeneity of these published studies have also generated some doubts on the issue.
The aim of our narrative review is to describe the main attributes of vitamin D metabolites and to define their role in daily clinical practice, with the aim of aiding physicians in choosing adequate strategies to use in patients with proven vitamin D deficiency or with a risk of hypovitaminosis D.