Describe the process by which the body converts sunlight to active vitamin D in the body. Discuss ...

Our bodies can synthesize vitamin D by using energy from exposure to sunlight. The process of converting sunlight into vitamin D begins when the ultraviolet rays of the sun convert a cholesterol compound in our skin (7-dehydrocholesterol) into cholecalciferol, a precursor of vitamin D (also called provitamin D3). The inactive form of cholecalciferol travels to the liver where it is converted to calcidiol. Calcidiol travels to the kidney, where it is converted into calcitriol, which is considered the primary active form of vitamin D in our bodies. Calcitriol made by the kidneys is found in the blood and acts in the intestine and bone to promote calcium metabolism. Calcitriol made by other cells in the brain, breast, prostate, pancreas, and colon acts locally to promote calcium metabolism.