Ultraviolet rays react with cholesterol in the skin to begin the process of forming vitamin D, Cholesterol is a sterol, which is found in body tissues and in the blood plasma, it is transformed, by the sun UV rays into ergocalciferol, a vitamin D, necessary for the absortion of other vitamins such as calcium, important for bone health, and to regulate the leves os phosphorus in blood. A deficiency of vitamin D in the body could generate great bone damages such as rickets, osteomalacia or even osteoporosis in a long term.
