ergocalciferol

biochemistry

Also known as: calciferol, vitamin D2

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Last updated

June 26, 2026

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Ergocalciferol, also known as vitamin D₂, is a form of vitamin D derived from ergosterol, a steroid found in fungi. It is produced when ergosterol is exposed to ultraviolet radiation. Ergocalciferol is important for calcium metabolism in animals and promotes proper bone development. It is used as a dietary supplement and medicinally to treat rickets, a bone disorder caused by vitamin D deficiency. While vitamin D₂ and vitamin D₃ (cholecalciferol) are similar in human metabolism, D₂ is less effective in birds.123

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vitamin D
…plants and better known as ergocalciferol (or calciferol), and vitamin D₃, found in animal tissues and often referred to as cholecalciferol. Both of these compounds are inactive precursors of potent metabolites and therefore fall into the category of prohormones. This is true not only for cholecalciferol and ergocalciferol obtained from…
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…plants and better known as ergocalciferol (or calciferol), and vitamin D₃, found in animal tissues and often referred to as cholecalciferol. Both of these compounds are inactive precursors of potent metabolites and therefore fall into the category of prohormones. This is true not only for cholecalciferol and ergocalciferol obtained from…
Read More