Influence of long chain unsaturated fatty acids in formula feeds on lipid peroxidation and antioxidants in preterm infants.

The influence of long chain polyunsaturated fatty acids (LCP) in formula feeds on lipid peroxidation and antioxidants was studied in 35 healthy preterm infants (gestational age 30-35 wk) during the first 6 postnatal weeks. Infants received a preterm formula supplemented with n-3 LCP (LCP group, n = 13), or standard preterm formula (NO-LCP group, n = 15); 7 infants fed human milk served as a reference group. With LCP supplementation, erythrocyte C22:6n-3 levels were stable; without supplementation, the levels declined (difference p < 0.001). LCP supplementation did not decrease vitamin E or C levels, or increase lipid peroxidation products (thiobarbituric acid-reactive substances) in plasma. In erythrocytes, LCP supplementation did not markedly influence the reduced/oxidized glutathione ratio; however, the susceptibility to H2O2-induced oxidative stress was reduced. Our results suggest that healthy preterm infants are able to cope with any extra peroxidative stress produced by n-3 LCP supplementation. However, these findings might not be generally applicable to other formulas containing LCP supplements.