Positive Health Online

Abstract

MCDANIEL and co-authors, Department of Psychology, University of New Mexico, Albuquerque, New Mexico 87131, USA, msdaniel@unm.edu, have reviewed (117 references) the question of 'brain-specific' nutrients and hopes of a 'memory cure'.

Background

Some widely-marketed compounds are claimed to be memory enhancers and treatments for age-related memory deterioration. This review was limited to double-blind placebo controlled studies in order to evaluate these claims.

Methodology

Compounds examined in this review are phophatidylserine (PS), phosphatidylcholine (PC), citicoline, piracetam, vinpocetine, acetyl-L-carnitine (ALC), and antioxidants, particularly vitamin E.

Results

In animal studies, PS has been shown to attenuate many neurological effects of ageing and restore normal memory for a variety of tasks. Preliminary findings with humans are however limited. For older people with moderate cognitive impairment, but not for Alzheimer's patients, PS has produced modest increases in recall of word lists, but not consistently for other memory tests. Equally, PC and citicoline have not proven effective in patients with Alzheimer's disease. The issue in older people without serious degenerative disease remains open. Piracetam has been assessed in animal studies and looks promising in terms of improving neuronal activity, but there is no conclusive evidence for benefit in humans. Vinpocetine increases blood circulation and metabolism in the brain, and in older adults suffering from memory problems associated with poor brain circulation, vinpocetine significantly improves performance in cognitive tests reflecting attention, concentration, and memory. ALC is involved in cellular energy production and in removal of toxic accumulation of fatty acids. Studies in patients with Alzheimer's disease show nominal improvements but rarely significant advantages over placebo. The compound has not been tested in people without brain disease. Antioxidant vitamins are expected to slow down degenerative processes, but studies show no effect on memory decline or improvement of students' performance in cognitive tests.

Conclusion

In the 'brain-specific' nutrients reviewed here, a few mildly suggestive effects have been found. It is suggested that future evaluation of these supplements should focus more on memory processes rather than on memory tests per se.

References

McDaniel MA, Maier SF, Einstein GO. 'Brain-specific' nutrients: a memory cure? Nutrition 19 (11-12): 955-956, Nov-Dec 2003.