Antioxidant Function and Health Implications of Vitamin E
Ching Kuang Chow*, 1, Hannah S Chow-Johnson2
Identifiers and Pagination:Year: 2013
First Page: 1
Last Page: 6
Publisher Id: TONUTRJ-7-1
Article History:Received Date: 12/10/2012
Revision Received Date: 09/11/2012
Acceptance Date: 12/11/2012
Electronic publication date: 24/1/2013
Collection year: 203
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Superoxide, a key precursor of important reactive oxygen/nitrogen species (ROS/RNS), may release iron from its protein complex. By mediating the generation and/level of superoxide, vitamin E, the most important fat-soluble anti-oxidant and free radical scavenger, may exert its antioxidant function by limiting the formation of reactive hydroxyl radi-cals and peroxynitrite. The antioxidant function of vitamin E is augmented by GSH peroxidase and related metabolic sys-tems which respond adaptively and compensatively to oxidative stress. By mediating the levels of ROS/RNS, vitamin E may also modulate the activation and/or expression of redox-sensitive biological response modifiers, and thereby attenu-ate the cellular events leading to the onset and development of aging and other degenerative disorders. Earlier epidemiol-ogical data and retrospective studies show an association between increased intake of vitamin E and reduced risk of car-diovascular disease, cancer, and other disorders. However, subsequent prospective randomized placebo-controlled studies and interventional trials have provided inconsistent findings. Data available from recent large-scale interventional trials suggest that vitamin E supplements at high doses are not beneficial.