   WHY DO YOU NEED VITAMIN D3   ?   Vitamin D 3 enhances calcium absorption and retention, a key nutritional role in supporting healthy bones, and may play a potential role in cardiovascular, colon and cellular health.  Vitamin D levels have been shown to decline with age, due primarily to a reduction in either absorption or metabolism by the liver. Decreased exposure to sunlight, a vegetarian diet, or a low intake of vitamin D fortified foods also play a role in inadequate vitamin D levels.*   CLINICAL USES FOR VITAMIN D3    Bone Health:  Vitamin D promotes intestinal calcium and phosphorous absorption and reduces urinary calcium loss, essential mechanisms for maintaining proper calcium levels in the body and for healthy bone composition. Clinical studies involving vitamin D supplementation suggest the importance of vitamin D in addition to calcium for bone health. Vitamin D supplementation alone may also support bone health.*   Cardiovascular Support:  Vitamin D may also provide cardiovascular support for some individuals, which may be attributed to its effect on calcium metabolism or possibly by helping to maintain healthy plasma renin function.*   Cellular Health:  Studies suggest vitamin D supports colon health by promoting healthy cellular function. 