provitamin


provitamin
A substance that can be converted into a vitamin; e.g., β-carotene.
- p. A trivial name for carotenoids exhibiting qualitatively the biologic activity of β-carotene, i.e., vitamin A precursors (α-, β-, and γ-carotene and cryptoxanthin); contained in fish liver oils, spinach, carrots, egg yolk, milk products, and other green leaf or yellow vegetables and fruits.
- p. D2 any substance that can give rise to ergocalciferol (vitamin D2); e.g., ergosterol.
- p. D3 SYN: 7-dehydrocholesterol.

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pro·vi·ta·min (')prō-'vīt-ə-mən n a precursor of a vitamin convertible into the vitamin in an organism <ergosterol is a \provitamin of vitamin D>

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n.
a substance that is not itself a vitamin but can be converted to a vitamin in the body. An example is b-carotene, which can be converted into vitamin A.

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pro·vi·ta·min (pro-viґtə-min) a precursor of a vitamin.

Medical dictionary. 2011.