Editorial Comment Role of vitamin D in vascular calcification: bad guy or good guy?

hypervitaminosis D The role of vitamin D and its derivatives in vascular calci-fication is complex. It has long been known that in humans, hypervitaminosis D may be associated with extensive arte-rial calcium phosphate deposits, mostly in the form of apa-tite crystals. In experimental animals, the administration of pharmacological doses of vitamin D sterols can lead to widespread arterial calcification, especially in association with favourable conditions such as atherosclerosis, diabetes and chronic kidney disease (CKD) [1–5]. The mechanisms by which high doses of vitamin D or its derivatives induce vascular calcification include an in-crease in serum calcium and phosphate, the formation of fetuin-A mineral complexes in association with a decrease in free serum levels of fetuin-A [6] and the local inductio