title: The effect of antioxidant vitamins E and C on cognitive performance of the elderly with mild cognitive impairment in Isfahan, Iran: a double-blind, randomized, placebo-controlled trial.
abstract: OBJECTIVE
  This study was carried out to investigate the effect of vitamins E and C on cognitive performance among the elderly in Iran.
  
  
  METHODS
  About 256 elderly with mild cognitive impairment, aged 60-75 years, received 300 mg of vitamin E plus 400 mg of vitamin C or placebo daily just for 1 year.
  
  
  BACKGROUND
  Demographic characteristics, anthropometric variables food consumption, cognitive function by Mini-Mental State Examination (MMSE), and some of the oxidative stress biomarkers were examined.
  
  
  RESULTS
  Antioxidant supplementation reduced malondialdehyde level (P < 0.001) and raised total antioxidant capacity (P < 0.001) and glutathione (P < 0.01). The serum 8-hydroxydeoxyguanosine remained unchanged (P < 0.4). After adjusting for the covariates effects, MMSE scores following 6- (25.88 ± 0.17) and 12-month antioxidant supplementation (26.8 ± 0.17) did not differ from control group (25.86 ± 0.18 and 26.59 ± 0.18, respectively).
  
  
  CONCLUSIONS
  Despite significant improvement in most of the oxidative stress biomarkers, antioxidants' supplementation was not observed to enhance cognitive performance. A large number of kinetic and/or dynamic factors could be suspected.
authors: School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran.
authors: A M Alavi
authors: AM
authors: Naeini
authors: I
authors: I
authors: Elmadfa
authors: A
authors: A
authors: Djazayery
authors: M
authors: M
authors: Barekatain
authors: M R Aghaye
authors: MR
authors: Ghazvini
authors: M
authors: M
authors: Djalali
authors: A
authors: A
authors: Feizi
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000368:Aged; D000975:Antioxidants / Q000008:administration & dosage*; D001205:Ascorbic Acid / Q000008:administration & dosage*; D003071:Cognition / Q000187:drug effects*; D060825:Cognitive Dysfunction / Q000188:drug therapy*; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000097:blood; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D005978:Glutathione / Q000097:blood; D006801:Humans; D007492:Iran; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects; D014810:Vitamin E / Q000008:administration & dosage*
chemical_list: D000975:Antioxidants; D014810:Vitamin E; D008315:Malondialdehyde; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine; D005978:Glutathione; D001205:Ascorbic Acid