The 1993 Borden Award Lecture. Fatty acid requirements of the newborn.

Arachidonic acid (20:4 omega-6) and docosahexaenoic acid (22:6 omega-3) are deposited in large amounts in the nonmyelin membranes of the developing central nervous system (CNS). Inadequate supplies of omega-6 and omega-3 fatty acids during CNS development are of concern because of possible long-term changes in learning ability and reduced visual function. Although all of the omega-6 and omega-3 fatty acids in the CNS are ultimately derived from the diet, the pathways for transport or transfer from the plasma to the CNS are not known. Current evidence suggests that the newborn is able to synthesize 20:4 omega-6 and 22:6 omega-3 from linoleic acid (18:2 omega-6) and linolenic acid (18:3 omega-33), respectively; however, it is not yet clear if synthesis occurs in the liver prior to transfer to the CNS, or directly in the CNS. Further understanding of the roles of 20:4 omega-6 and 22:6 omega-3 in CNS metabolism, pathways of omega-6 and omega-3 fatty acid transport and CNS uptake, and the effects of premature birth on fatty acid metabolism is needed to facilitate future studies on the importance of 20:4 omega-6 and 22:6 omega-3 in infant nutrition.