Polyunsaturated fatty acid composition of human milk in France: changes during the course of lactation and regional differences.

Milk samples were collected 2-5, 15, 30, 60 and 90 days postpartum from 41 individual mothers recruited in three French cities in order to obtain a general view of the polyunsaturated fatty acid (PUFA) composition in France. Considering the overall results, linoleic acid (18:2 n-6) represented between 11.6% and 13% of total fatty acids in human milk. In contrast alpha-linolenic acid (18:3 n-3) accounted only for about 0.6%, and hence the 18:2 n-6 to 18:3 n-3 ratio was close to 20. Amounts of n-6 and n-3 long-chain PUFAs (LCPs) regularly decreased from postpartum days 2-5 (3.09%) to day 30 (1.67%), and then remained unchanged up to postpartum day 90; the n-6/n-3 LCP ratio ranged between 2.5 and 2. According to regional areas, there were significant differences (P < 0.05) only for colostrum contents of 18:3 n-3 and LCPs, the LCP ratio remaining unchanged. These data are discussed with regard to recent data on human milk fatty acid composition from Western countries and to the mechanisms involved in milk LCP balance.

Effect of two types of fish oil supplementation on plasma and erythrocyte phospholipids in formula-fed term infants.

We studied the effect of docosahexaenoic acid (DHA) supplementation of infant formulas on fatty acid composition of blood phospholipids in term infants. Two fish oil supplemented formulas containing 0.45 wt% DHA and high (0.35%) or low (0.10%) eicosapentaenoic acid (EPA) were fed for 42 days and compared with a standard formula and breast milk. Infants fed supplemented formulas and breast milk had similar time-dependent changes for DHA from birth to day 42, i.e., slight decreases in plasma phospholipids and erythrocyte phosphatidylcholine and no change in erythrocyte phosphatidylethanolamine. Low-EPA formula prevented EPA accumulation but did not limit the significant decrease in arachidonic acid (AA) noted in infants fed high-EPA formula. These results suggest that term infant formulas should be supplemented with DHA-rich EPA, low fish oil and AA to achieve a fatty acid status in formula-fed infants similar to that of breast-fed infants.