Vitamin D, calciferol, is not a vitamin. In the skin, Vitamin D is produced following exposure to ultraviolet radiation. It is then called cholecalciferol. In our diet, vitamin D is available as ergocalciferol. It is found in the oil of some fish, the liver of some mammals, and in fortified food.
Vitamin D is essential for normal growth and development in children.
Vitamin D deficient rickets. This type usually results from a dietary deficiency of vitamin D, usually coupled with inadequate exposure to sunlight. Hypophosphatemic vitamin D resistant rickets. It is caused by the inadequate re-absorption of phosphate in the proximal tubule of the kidneys. Affected children have a very short stature, with dramatic bowing of the legs.