Positive Health Online

Abstract

HAAG, Department of Physiology, University of Pretoria, PO Box 2034, Pretoria 0001, South Africa, mhaag@medic.up.ac.za, has reviewed (99 references) essential fatty acids and the brain.

Background

The aim of the paper is to review the role of essential fatty acids in brain function and in the genesis of psychiatric disease.

Methodology

An extensive literature search was performed.

Results

The fatty acid composition of the cell membranes of nerve cells in the brain reflects dietary intake of various fatty acids. The degree of desaturation of the fatty acids (ie the number of double bonds) determines the fluidity of cell membranes and thus the function of nerve cells. In addition, it is thought that n-6 polyunsaturated fatty acids give rise to prostaglandins, substances involved in inflammatory processes. A higher intake of n-6 polyunsaturates can thus lead to a higher potential for inflammatory processes to occur in the nervous system. The ratio between n-3 and n-6 polyunsaturates may influence various aspects of serotoninergic and catecholaminergic neurotransmission (ie the transmission of nerve signals involving the neurotransmitters serotonin and noradrenalin or adrenalin). Clinical trials have shown that n-3 polyunsaturated fatty acids in the diet may have a beneficial effect in the treatment of various psychiatric disorders, but data are inconclusive at present.

Conclusion

The ratio of n-3 to n-6 polyunsaturated fatty acids can be modulated by diet. This ratio influences neurotransmission and prostaglandin formation, processes that are vital in the maintenance of normal brain function.

References

Haag M. Essential fatty acids and the brain. Canadian Journal of Psychiatry 48 (3): 195-203, Apr 2003.

Comment

The jump between basic membrane biochemistry and psychiatric disease is quite big, and some of the assumptions underlying this article would appear rather rash.