Requirements for long-chain polyunsaturated fatty acids in the preterm infant

Dietary long-chain polyunsaturated fatty acids have demonstrable beneficial effects on early development. The effects on neural development are of particular interest. Human milk is the best and only time-proven source of fat and essential fatty acids in the infant diet. Technologic procedures based on chemical and physical separation of the unsaturated fatty acids have permitted the isolation of concentrated sources of docosahexaenoic acid and arachidonic acid for clinical use. Virtually all infant formulas in developed countries have increased the levels of gamma-linolenic acid, and several manufacturers in Europe and in Japan have added docosahexaenoic acid, or docosahexaenoic acid plus arachidonic acid, or have also included gamma-linolenic acid in formulas for preterm and term infants. The efficacy of this practice for preterm infants seems fairly well established. The use of stable isotope methods to evaluate biosynthesis of long-chain polyunsaturated fatty acids from dietary precursors may help to better define optimal amounts and relationships of fatty acids in infant formula.