The story of a vitamin for bone health that upgraded to hormone for systemic good health.

The discovery of Vitamin D is a multi-step history started in 1650 and culminated in 1963 with the determination of its chemical structure. The diffusion of rickets in North Europe and North America was the first reason for experimental studies. Nevertheless, in the last decades new potential actions have been revealed. Besides bone and intestine, the Vitamin D receptors have been demonstrated in different organs such as the brain, prostate, breast, colon, immune system cells, smooth muscle and heart.
Not totally fulfilling the criteria of a vitamin, Vitamin D is actually considered a pleiotropic hormone with endocrine and paracrine actions. The current evidences support the role of Vitamin D in skeletal health and suggest that the treatment of Vitamin D deficiency should be desirable to reduce the risk of chronic health diseases.