Human milk long-chain polyunsaturated fatty acids

No differences in blood plasma TAC were found after 30 days of feeding low-birth-weight infants with a formula containing n-6 and n-3 long-chain polyunsaturated fatty acids (LCP) from purified phospholipids as compared with a group fed human milk (Rl). Cyclic voltammetry of blood plasma of 2- to 4-month-old infants did not reveal any differences in the antioxidant capacity between breast-fed and modified cow milk formula-fed infants (G15). 

The major differences between the lipids of bovine and human milk are in fatty acid composition and triacylglycerol structure. Bovine milk contains substantial quantities of C4 o-Ci0 o, about 2% Cis 2 and almost no other long-chain polyunsaturated fatty acids. The fatty acid composition is not altered by ordinary changes in diet. Human milk contains very little C4 o-C10 o, 10-14%i (w/w of fat) Ci8 2, and small quantities of other polyunsaturates. The triacylglycerol structure differs, with much of the sn-2 position in human milk lipids occupied by C16 0 and the sn-2 position of bovine milk-fat occupied by C4 o-Ci0 o-... 

A fish oil supplement for infant formula has been shown to be effective at maintaining concentrations of co-3 long-chain polyunsaturated fatty acids in erythrocytes. Although human milk contains only small amounts of long-chain polyunsaturated fatty acids, it contains all the w-6 and w-3 fatty acids found in erythrocyte membranes. Carlson et al. (1987) demonstrated that if infant formula is supplemented with fish oil rich in EPA (C20 5, o>-3) and DHA (C22 6, w-3), levels of these polyunsaturated fatty acids can be maintained post-birth, in erythrocyte membranes. These results indicate the effectiveness of providing long-chain polyunsaturated fatty acids directly in the diet rather than as precursors. 

The mammary gland produces milk, which is the major source of nutrients for the breastfed human infant. The fatty acid composition of human milk varies, depending on the diet of the mother. However, long-chain fatty acids predominate, particularly palmitic, oleic, and linoleic acids. Although the amount of fat contained in human milk and cow s milk is similar, cow s milk contains more short- and medium-chain fatty acids and does not contain the long-chain, polyunsaturated fatty acids found in human milk that are important in brain development. 

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