Conjugated linoleic acid concentrations of human milk and infant formula

Conjugated linoleic acid (CLA) is an anticarcinogen found in ruminant products. CLA may also act as a growth promotor in the neonate. Because of the potential importance of CLA to maternal and infant health, CLA concentration was quantified in human milk and infant formula. Human milk samples (n = 14) were collected by complete breast expression, and four brands of formula were analyzed; both powder and ready-to-feed products were studied. Although CLA was detected in only 31% of the formula samples, it was detectable in all human milk. Concentration of the biologically important isoform (c9,t11) of CLA in human milk ranged from 2.23 to 5.43 mg/g fat, that of formula from undetectable to 2.04 mg/g fat. Percent total CLA present as c9,t11 ranged from 83 to 100% in human milk and 80 to 100% in formula. Overall, human milk contained significantly more (P < 0.0001) CLA than did the samples of infant formula containing measurable concentrations (3.64 +/- 0.93 vs. 1.35 +/- 0.81 mg/g fat, respectively). (C) 1997 Elsevier Science Inc.