What vitamin D does
Vitamin D is one of several substances called vitamins, which the body needs to grow and develop normally. Vitamin D is famous for its role in helping the body absorb the calcium needed for strong bones and in maintaining an adequate level of calcium in the blood. A deficiency of vitamin D leads to a softening of the bones that in children is called rickets and in adults osteomalacia.
Vitamin D also plays a role in promoting cell growth, in building our immune function, and in reducing inflammation. New research is studying the role these activities may play in the development of several chronic diseases, including heart disease, multiple sclerosis, and diabetes. Checking the patient’s vitamin D status is becoming a common laboratory test ordered by doctors, and levels less than 30 nanomoles per liter (nmol/l) of blood indicates a deficiency.