The pro-oxidant activity of high-dose vitamin E supplements in vivo.
BACKGROUND
A recent meta-analysis has demonstrated that the regular administration of high-dose vitamin E supplements may be associated with increased mortality. The biological mechanism for this effect is uncertain.


METHODS
A ferrous oxidation xylenol assay was used to assess plasma oxidation activity levels in samples from a randomized, placebo-controlled, 6-week trial of daily vitamin E supplementation in adults with asthma (n = 72).


CONCLUSIONS
A 27% increase in plasma oxidation activity levels was observed in patients receiving vitamin E. We demonstrate a pro-oxidant effect of high-dose vitamin E supplementation that may explain the increase in mortality observed in intervention studies using this nutrient.
Pearson
Philip
P
Division of Respiratory Medicine, University of Nottingham, Nottingham City Hospital, Hucknall Road, Nottingham, UK.
Lewis
Sarah A
SA
Britton
John
J
Young
Ian S
IS
Fogarty
Andrew
A
D000293:Adolescent; D000328:Adult; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D015227:Lipid Peroxidation; D008297:Male; D008875:Middle Aged; D009026:Mortality; D010084:Oxidation-Reduction; D017382:Reactive Oxygen Species / Q000627:therapeutic use*; D014810:Vitamin E / Q000627:therapeutic use*
D017382:Reactive Oxygen Species; D014810:Vitamin E