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

Eur J Nutr. 2014 Aug;53(5):1255-62. doi: 10.1007/s00394-013-0628-1. Epub 2013 Dec 11.

Abstract

Purpose: 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).

Conclusion: 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.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 8-Hydroxy-2'-Deoxyguanosine
  • Aged
  • Antioxidants / administration & dosage*
  • Ascorbic Acid / administration & dosage*
  • Cognition / drug effects*
  • Cognitive Dysfunction / drug therapy*
  • Deoxyguanosine / analogs & derivatives
  • Deoxyguanosine / blood
  • Dietary Supplements*
  • Double-Blind Method
  • Female
  • Glutathione / blood
  • Humans
  • Iran
  • Male
  • Malondialdehyde / blood
  • Middle Aged
  • Oxidative Stress / drug effects
  • Vitamin E / administration & dosage*

Substances

  • Antioxidants
  • Vitamin E
  • Malondialdehyde
  • 8-Hydroxy-2'-Deoxyguanosine
  • Deoxyguanosine
  • Glutathione
  • Ascorbic Acid