Vitamin D3 also known as cholecalciferol is one of the two major forms of Vitamin D, which is not only essential for skeletal growth but have been found to help other organ systems as well such as the Endocrine system. Studies suggest that Vitamin D may also lower the risk of cancer however some critics believe that these studies are not conclusive.
There are different types of Cholecalciferol that takes effect in our bodies. Calciol,the inactive form of vitamin D3, calcifediol also known as 25-hydroxycholecalciferol and the active form of vitamin D3, calcitriol. Through ultra violet radiation, 7-dehydrocholesterol, a cholesterol steroid, forms in the epidermal layer of the skin, particularly in the stratum germinativum and stratum spinosum which converts it to calciol. This form of Vitamin D3 is then sent to the liver where it becomes calcifediol which is then released into the blood
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stream. The kidneys then absorb the calcifediol and the hormone calcitriol is produced.
Calcitriol is essential for the normal absorption of calcium and phosphorus by the digestive tract, stimulating the formation of osteoprogenitor cells and osteoclasts, stimulating bone resorption and suppressing parathyroid hormone production (when
Vitamin D levels are low, parathyroid hormone or PTH restores the calcium levels by reabsorption of calcium in the kidneys and bones).
Vitamin D is normally produced in the skin after exposure to sunlight. Ultra Violet-B radiation, as mentioned above is the most natural means of Vitamin D absorption. However; many factors affect the amount of absorption that is actually received from sunlight. One example is the pigmentation of the skin, the melanin. Melanin acts as a sunscreen protecting our skin from harmful rays but at the same time also reducing the amount of UVB radiation we are exposed to, eventually decreasing the amount of Vitamin D produced. Therefore the darker the...