- Supports strong bones, mineral balance, and gene regulation.
- Fortifies the immune system and supports cell growth.
Vitamin D is a fat soluble vitamin found in some plant and animal sources, but primarily produced by the body after exposure to the sunís ultraviolet (UV) rays. UV rays promote the skinís production of vitamin D. Vitamin D3 or calciferol is the most active form, while vitamin D2 or ergocalciferol is synthesized by plants and less available to humans (in fact, studies cited in the Journal of Clinical Endocrinology & Metabolism, indicate that Vitamin D3 is 87% better in humans, in terms of absorption and bioavailability, than D2).
Vitamin D functions primarily to maintain normal blood levels of calcium and phosphorus. By supporting healthy calcium absorption, vitamin D helps to maintain strong bones. Vitamin D also works synergistically with other vitamins, minerals, and hormones to promote bone mineralization. Unfortunately with aging, skin cannot synthesize vitamin D from the sun as efficiently.
Vitamin D has more recently been in the spotlight for immune system support. Vitamin D is thought to promote immune health by supporting regulation of cell growth and differentiation—the process that determines cellís ďjobĒ in the body. This regulation is particularly important as the differentiation of cells leads to a decrease in proliferation. Cellular proliferation, while essential for growth and wound healing, may foster harmful mutations, if uncontrolled.
Vitamin D has also shown great promise in maintaining the bodyís innate immune response as well as supporting appropriate autoimmune activity. Both these mechanisms are thought result from vitamin Dís regulation of T cell development.
More recent studies also suggest that Vitamin D may play a role in supporting healthy body fat levels.
- Vitamin D may worsen hypercalcemia.
- Hypercalcemina may contribute to arteriosclerosis, particularly in persons with kidney disease. Such members should use supplemental vitamin D cautiously.