VITAMIN D helps to absorb calcium from the intestinal tract, maintain proper serum (blood) calcium levels, as well as deposit calcium in the bones and teeth. Furthermore, Vit D interacts with Vit A and the thyroid to support healthy cell growth and differentiation. Thus it helps to build healthy tissue and promote development and activation of white blood cells, necessary for a healthy immune system.
Vit D may ward off or reduce the incidence of cancer by inhibiting uncontrolled growth of abnormal and/or poorly developed cells.
Vit D deficiency is quite prevalent, especially in the elderly whose digestion is often impaired. Exposure to sunlight allows the skin to make Vit D which is stored in the liver and activated in the kidneys when needed by the body. The ability to utilize sunlight in this manner is lessened in many elderly people. However, even young people and sunbathers may not be able to profit from this mechanism if they use sunscreen lotion with an SPF greater than 8. Knocking out this important source of Vit D makes us more dependent on supplements to make up for this loss.
The hallmark of Vit D deficiency is soft, malformed bones (click on any picture for larger image). Children are particularly vulnerable to deformity of the legs, called rickets, manifesting in bow leggedness because they are in great need of this vitamin, which promotes healthy cell growth and development. Other symptoms of childhood Vit D deficiency are a delayed loss of baby teeth, irritability and restlessness, delayed development of motor skills, as well as impaired development of bones and muscles.
In adults, a Vit D deficiency may manifest in osteomalacia (weakness and deformity of bone), osteoporosis, as well as weakness in the pelvis and hips, leading to difficulty with standing up, climbing stairs, and an unsteady gait. Because Vit D supports a healthy immune system, a deficiency results in an increased susceptibility to infections and repeated infection. There’s a potential for increased blood pressure, and a greater tendency for developing colon and breast cancer.