Is beta-carotene an antioxidant?
An hypothesis is presented that is opposed to the conventional viewpoint that beta-carotene is an in vivo free-radical scavenger. It is suggested that there are biochemical reasons why beta-carotene, other carotenoids, and especially their metabolites may be harmful to mammalian systems. Finally, the hypothesis that the macular pigment carotenoids, lutein and zeaxanthin, are free-radical scavengers is challenged.
Crabtree
D V
DV
Schepens Eye Research Institute, Harvard Medical School, Boston, MA 02114, USA. crabtree@vision.eri.harvard.edu
Adler
A J
AJ
D000818:Animals; D000975:Antioxidants; D002338:Carotenoids / Q000378:metabolism*; D016166:Free Radical Scavengers; D006801:Humans; D014975:Lutein / Q000378:metabolism; D008322:Mammals; D008954:Models, Biological; D012160:Retina / Q000502:physiology; D024341:Xanthophylls; D065146:Zeaxanthins; D019207:beta Carotene / Q000031:analogs & derivatives / Q000378:metabolism / Q000502:physiology* / Q000633:toxicity*
D000975:Antioxidants; D016166:Free Radical Scavengers; D024341:Xanthophylls; D065146:Zeaxanthins; D019207:beta Carotene; D002338:Carotenoids; D014975:Lutein