Abstract

Docosahexaenoic acid (DHA) is a long-chain omega-3 fatty acid derived from the precursor alpha-linolenic acid. DHA, together with arachidonic acid, is the most highly concentrated polyunsaturated fatty acid in the nervous system. It has been suggested that DHA has an important role during the formation and in the function of the nervous system, particularly in the brain. Although the mechanism of action of DHA has not been totally elucidated, it has been suggested a role for the fatty acid at membrane level by regulating its functions, and at the genetic level by the regulation of the expression of some genes involved in the brain function. The content of DHA of the brain has been correlated to the learning ability and the intelligence level of newborn and nursing babies. Several experimental reports in animals and in humans have demonstrated the need for the fatty acid during brain development. The fatty acid, formed from the precursor, supplied by the diet, and from the tissue reservoirs, is provided by the mother to the foetus during the pregnancy and to the newborn through the milk during the lactating period. It has been suggested the need for DHA supplementation during the gestational period, and even before, to secure an adequate supply of the fatty acid for the brain development. DHA supplementation can be provided through oils with high content of the fatty acid, as phospholipids, as ethyl ester derivatives of the fatty acid, or as DHA-containing monoglycerides. The evidence for a role of DHA during the brain development and function, and the relation of the fatty acid with the learning capability and intelligence of newborn babies is discussed. The different ways to supply DHA to the mother during pregnancy and to the newborn during lactation are also discussed.