Lipid Metabolism of Korean Breast-Fed Formula-Fed Infants

모유영양아와 인공영양아의 지질 대사

The difference in lipid metabolism between breast-fed(BF) and formula-fed(FF) infants were studied in 31 Korean infants at 1, 2 and 3 months postpartum. The formulas had more total lipids(TL), triglycerides(TG) and phospholipids and less cholesterol(CHOL) and free fatty acids(FFA) than the breast milk. The milk consumption of the FF infants was significantly greater than that of the BF infants with a wide individual variation. As a result, the FF infants appeared to consume more TL, TG and PL and less CHOL and FFA than the BF infants during 3 months. The lipid contents of the breast milk tended to decrease in due course of lactation, therefore the intake of lipids of BF infants was reduced during the first three month of lactation. The plasma TG and CHOL levels of infants at 3 month were not significantly different between the BF and FF infants, but the PL level of the BF infants was higher then that of the FF infants. The plasma levels of TG and CHOL were not significantly correlated with the intakes of TL, TG, CHOL, PL and FFA, respectively. The PL level, however, was positively correlated with the intakes of CHOL and FFA, respectively and negatively correlated with PL intake as well as 18 : 2w6 fatty acid content of the breast milk or the formulas. The fecal weight and fecal loss of TL of the FF infants were greater than those of the BF infants during 3 months, however, apparent lipids digestibility was not significantly different between the BF and FF infants. The fecal excretions of CHOL and bile acids of FF infants were substantially higher than those of BF infants during 3 months. New sterol balance showed a particularly large difference between the BF and FF infants. The value of the net sterol balance of the BF infants was negative, but that of the FF infants was positive. This study shows that the consumption pattern of various lipid components of BF and FF infants were different as a result of different lipid compositions between breast milk and formula. The significantly lower sterol balance of the BF infants than the FF infants may have been derived from the unique dietary characteristic of breast milk.