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beta carotene
be·ta car·o·tene also be·ta-car·o·tene B0213100 (bā′tə-kăr′ə-tēn′, bē′-)n. The isomeric form of carotene that is most widely distributed in nature and is efficiently converted to vitamin A by the body.be′ta car′otene
n. the most abundant of various isomers of carotene, C40H56, that can be converted by the body to vitamin A. be·ta carotene (bā′tə) A form of carotene widely found in plants and animals. Beta carotene is most efficiently converted to vitamin A in the liver.beta carotene
beta carotene[′bād·ə ′kar·ə‚tēn] (biochemistry) C40H56 A carotenoid hydrocarbon pigment found widely in nature, always associated with chlorophylls; converted to vitamin A in the liver of many animals. beta carotene
carotene [kar´o-tēn] a yellow or red pigment found in many dark green, leafy, and yellow vegetables such as collards, turnips, carrots, sweet potatoes, and squash, as well as in yellow fruit, milk, egg yolk, and body fat; it is a chromolipoid hydrocarbon existing in four forms (α-, β-, γ-, and δ-carotene), which can be converted into vitamin A in the body.beta carotene 1. the β isomer of carotene.2. a preparation of this substance administered orally to prevent vitamin A deficiency and to reduce photosensitivity in patients with protoporphyria" >erythropoietic protoporphyria. Written also betacarotene and β-carotene.beta carotene also beta-carotene (bā′tə-kăr′ə-tēn′, bē′-)n. The isomeric form of carotene that is most widely distributed in nature and is efficiently converted to vitamin A by the body.beta caroteneA yellow-orange pigment found in fruits and vegetables; it is the most common precursor of vitamin A. The daily human requirement for vitamin A can be met by dietary intake of beta carotene. ToxicityIngestion of large doses of vitamin A either acutely or chronically causes skin and liver damage, among other injuries. Beta carotene supplements increase the risk of death among smokers and have no known beneficial effects on nonsmokers. Beta carotene occurring naturally in foods has no known toxicity. BenefitsA diet rich in beta carotene has been associated with a decreased risk of certain cancers. DosingVitamin A activity in foods is expressed as retinol equivalents (RE). Six mg of beta carotene equals 1 µg of retinol or 1 RE. See: vitamin A; retinolbeta carotene A precursor of vitamin A.ThesaurusSeebeta-carotene |