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Etymology: Gk, beta; L, carota, carrot
a vitamin A precursor and ultraviolet screening agent.
indication It is prescribed to ameliorate photosensitivity in patients with erythropoietic protoporphyria.
contraindications It is used with caution in patients with impaired renal or hepatic function. Known hypersensitivity to this drug prohibits its use.
adverse effects No serious adverse reactions have been observed. Diarrhea may occur.
beta-caroteneA natural red-orange fat-soluble retinoid provitamin metabolised to vitamin A in the body; it is an antioxidant and free-radical scavenger, protecting cells against oxidation damage linked to cancer; it is present in fresh fruits and vegetables, and has immunostimulatory activity; increased BC consumption is associated with a decreased risk of bladder, colon, lung, skin cancer and cancer cell growth in vitro.
Minor protection against heart disease, strokes and effects of ageing.
beta-caroteneprecursor of vitamin A, usually ample in a normal diet, which is converted in the body to retinol. This and other carotenoids also function as antioxidants, protecting cells against oxidation damage. Beta-carotene supplements do not appear to have any ergogenic effect. Thus, it is recommended that this pro-vitamin is best obtained through the diet. See also vitamins; appendix 4.2 .
n a plant pigment, antioxidant, and biochemical precursor to vitamin A. Large doses may increase the risk of lung cancer and cardiac disease.