How vitamin D works on bone.

Vitamin D is important for the normal development and maintenance of bone. The elucidation of the vitamin D activation pathway and the cloning of the vitamin D receptor have advanced our understanding of the actions of vitamin D on bone. The preponderance of evidence indicates that 1,25(OH)₂D₃ enhances bone mineralization through its effects to promote calcium and phosphate absorption. Although 1,25(OH)₂D₃ stimulates bone resorption in vitro, treatment in vivo can prevent bone loss and fracture through several potential mechanisms. The development of vitamin D analogues has provided new therapeutic options for increasing bone mineral density and reducing fractures.