ASSESSMENT OF THE EFFICACIOUS DOSE OF ARACHIDONIC AND DOCOSAHEXAENOICACIDS IN PRETERM INFANT FORMULAS - FATTY-ACID COMPOSITION OF ERYTHROCYTE-MEMBRANE LIPIDS

The nutritional requirements of preterm infants for the long chain pol yunsaturated essential fatty acids, arachidonic acid (AA) and docosahe xaenoic acid (DHA), have not been clearly defined. The present study e valuated preterm infants of less than 2.3 kg birth weight fed a commer cial formula (Preemie SMA (R)) devoid of AA and DHA and compared this control group with similar infant groups fed one of three formulas con taining a range of 0.32 to 1.1% AA and 0.24 to 0.76% DHA. An analogous group of infants fed their mothers' breast milk and a breast milk for tifier (when indicated) was also studied. Erythrocyte membrane phospho lipids were isolated from blood samples collected at 12 d of age and a fter a further 4 wk of feeding. Infants fed the formula without AA and DHA showed a reduction in AA level in erythrocyte phosphatidylcholine , and a reduced level of DHA in phosphatidylethanolamine in comparison with infants fed breast milk or infant formula containing AA and DHA. Supplementing infant formula with increasing levels of AA and DHA pro duced a clear dose response in the levels of AA and DHA found in eryth rocyte membrane phospholipids. From comparison of membrane phospholipi d fatty acid composition it appears that a formula level of 0.32-1.1% AA and 0.24-0.76% DHA provides sufficient levels of these fatty acids to achieve a similar fatty acid composition to that of infants fed hum an milk for most of the lipid fractions examined.