Long-chain polyunsaturated fatty acids in infant nutrition: effects on infant development.

In the past year, two groups of investigators reported the effects of feeding n-3 and n-6 long chain polyunsaturated fatty acids on term-infant development. In general, these small randomised studies, along with two recent large randomised clinical trials, one with preterm and one with term infants, confirm and extend data on efficacy from smaller clinical studies reported in the past ten years. In addition, two independent systematic reviews published this year evaluated all but the most recent studies. Both systematic reviews concluded that there were benefits of feeding long chain polyunsaturated fatty acids to preterm infants in the short-term and acknowledged the absence of studies to address their effects on long-term visual development in infants. The continuing controversy as to the need for long chain polyunsaturated fatty acids by term infants is highlighted by the different conclusions reached in the systematic reviews. A middle view can also be supported by the data; that is, that fewer term infants than preterm infants can benefit from these fatty acids because of greater long chain polyunsaturated fatty acid accumulation in utero. Differences in intrauterine accumulation of these fatty acids may also play a role in inconsistent results among term studies.