Vitamin D and its role (not only) in osteology

Vitamin is a substance that has long been known and, in osteology, considered essential for a healthy development and subsequent

metabolism of bone tissue. However, only recently have some details of its effect on bone tissue been elucidated. The active form of

vitamin D (calcitriol) stimulates the production of RANKL, thus activating osteoclasts and simultaneously affecting the plasticity of

pluripotent mesenchymal cells and the stimulation of genes involved in osteoblast transformation. However, vitamin D is also involved

in a number of other processes in the organism. Of major importance is the interaction between vitamin D and the immune system.

Vitamin D affects both the resistance against bacterial infections and autoimmunity. Observational studies show an inverse correlation

between the incidence of type 1 diabetes and the saturation of the organism with vitamin D; however, this inverse correlation

is also found in type 2 diabetics. The links between vitamin D in the organism and the development or progression of tumour are

potentially very serious. The largest body of data in this area is related to vitamin D deficiency and the development of alimentary

tract and breast cancers.

Keywords: vitamin D, bone metabolism, immunity, diabetes mellitus, tumour proliferation