PLASMA AND RED-BLOOD-CELL FATTY-ACID COMPOSITION IN SMALL-FOR-GESTATIONAL-AGE TERM INFANTS FED HUMAN-MILK OR FORMULA

The purpose of the present study was to evaluate the effects of feedin g human milk or milk formula on the fatty acid composition of plasma a nd red blood cell (RBC) lipids in at term small for gestational age in fants (SGA) for the first 3 months of life. One group of infants recei ved a formula with a linoleic:alpha-linolenic acid ratio of 10:1 (MF g roup). Another group served as control and received their own mother's milk (HM group). Blood samples were taken at birth and at 1 week, 4 w eeks, and 3 months of life. Plasma and RBC fatty acid composition were analyzed by gas liquid chromatography and results of total plasma lip ids were expressed as concentrations by adding an internal standard. C oncentrations of saturated and monounsaturated fatty acids increased i n total plasma lipids with age in all infants. In contrast, those fatt y acids decreased when results were expressed as percentages of total fatty acids. Long-chain polyunsaturated fatty acids (LCP) decreased re gardless of how results were expressed, but the absolute concentration s of these fatty acids in plasma available for tissue accretion were g reater than suggested by the percentage results. Plasma and RBC docosa hexaenoic acid (22:6n-3) decreased in the MF group in comparison to th e HM group. Arachidonic acid (20:4n-6)was lower in plasma of MF-fed in fant but not in RBC phospholipids. We conclude that term SGA infants f ed an adapted milk formula with a linoleic:alpha-linolenic acid ratio of 10:1 but devoid of LCP may lead to a low n-3 LCP status.