CHOLECALEIFEROL, ERGOCALCIFEROL, IN THEORY----

vitamin D refers to two biologically inactive precursors - - D3, also known as Cholecalciferol, and D2, known as Ergocalciferol. The former is produced in the skin on exposure to UVB radiation (290 to 320 n m ) and can also be consumedfrom oily fish. The latter is derived from plants and only enters the body via the diet. Both D3 and D2 precursors are hydroxylated in the liver and kidneys to form 25- hydroxy vitamin D< the non-active "storage" form, , and 1,25 - dihydroxyvitamin D, the biologically active form that is tightly controlled by the body.


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a report from Decision News Media SAS.