Vitamin D 1,25-dihydroxy, also known as calcitriol, is the active form of vitamin D in the body. Vitamin D is a fat-soluble vitamin that is primarily obtained through exposure to sunlight and certain foods.
Once vitamin D is consumed or synthesized in the skin, it undergoes several transformations in the liver and kidneys to become its active form, vitamin D 1,25-dihydroxy.
Vitamin D 1,25-dihydroxy plays a crucial role in regulating calcium and phosphate metabolism in the body. It helps to increase calcium absorption from the intestine, reabsorb calcium and phosphate from the kidneys, and mobilize calcium from bones when needed.
In addition to its role in bone health, vitamin D 1,25-dihydroxy also has other important functions in the body. It plays a role in immune system regulation, cell growth and differentiation, and has been linked to a reduced risk of certain types of cancer, cardiovascular disease, and autoimmune disorders.