. Effect of vitamin and trace-element supplementation on cognitive function in elderly subjects. Nutrition. 2001 Sep;17(9):709-12. PubMed.

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  1. The validity of this article has been called into serious question by three journals. In January 2004, the British Medical Journal reported that its statistical reviewer concluded that the data in this trial had "all the hallmarks of being entirely invented." The BMJ also reported that the author holds the patent on this particular vitamin/mineral supplement and has since resigned from his position at Memorial University in St. John, Canada. Full text of the BMJ article.

  2. Brain Aging and Age-Related Neurodegenerative Diseases: Are Vitamin and Trace-element Supplementation the "Miraculous" Solution?
    Alzheimer’s disease (AD) is a common and complex neurodegenerative disease that affects approximately 15 million people worldwide (Geldmacher and Whitehouse, 1996; Mayeux and Sano, 1999). Aging is the major risk factor for a disease that coexists with other causes of cognitive decline, particularly vascular dementia (Hofman et al., 1997). At least 40 percent of elderly individuals in industrialized countries of North America and Europe have been estimated to have dietary intakes and blood-nutrient levels compatible with "deficiency" (Ames, 2004).

    Some studies indicate that vitamin E delays memory deficits in animal models (Ichitani et al., 1992; Socci et al., 1995). The Alzheimer’s Disease Cooperative Study completed a multicenter clinical trial of vitamin E plus selegiline supplementation of patients with moderate AD (Sano et al., 1997). The well-known results of this clinical trial indicate that treatment with vitamin E delays the time to important functional endpoints and suggest that vitamin E may slow disease progression in patients with moderately severe AD.

    More recently, Chandra (2001) performed a clinical trial where elderly people (> 65 years old) received a supplement of trace elements and vitamins or a placebo daily for 12 months. The author reported that after that period the supplemented group showed a significant improvement in all cognitive tests except long-term memory recall. The amounts of vitamin E and b-carotene were in amounts higher than those recommended for healthy adults. Although the author reported that no side effects or signs of overdose were observed, the duration of the study (12 months) was not sufficient to allow this conclusion. It is well known that toxicity can result from chronic use (high doses of a "toxic" agent in a short period of time) or acute use (lower doses of a "toxic" agent during a long period of time). A critical issue to resolve is the optimal dose of supplements that should be administered in volunteers for clinical trials. There are clinical studies indicating that high doses of vitamin E caused gastrointestinal complaints that either necessitated withdrawal of subjects from the study or reduction of the dose administered (Brin et al., 1989; Fahn, 1992). Although the benefits of antioxidants in AD are consistently shown, they must be considered together with safety of ingestion of vitamin and trace-element supplementation in excess of the recommend dietary allowance. Until more complete testes and doses are determined, physicians should avoid recommending mega-doses supplements to their patients.

    Paula I. Moreira, Catarina Oliveira, Maria S. Santos, Mark A. Smith, George Perry

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