Does breast feeding influence liver biochemistry?
OBJECTIVE
It is assumed that early feeding can affect liver biochemistry because breast-fed infants have a higher risk of hyperbilirubinemia than formula-fed infants. The authors sought to determine how feeding mode affected liver biochemistry in healthy term infants.


METHODS
Healthy term infants were followed up during infancy with a monthly questionnaire about feeding mode. Blood samples were obtained at 2, 6, and 9 months. Liver biochemistry (serum albumin, alkaline phosphatase, lactic dehydrogenase, aspartate aminotransferase [AST], and bilirubin), total insulin-like growth factor 1 (IGF-I), and insulin growth factor binding protein 3 (IGFBP-3) were determined at all ages.


RESULTS
Mean AST and bilirubin were significantly higher in breast-fed infants at 2 and 6 months. In addition, mean albumin levels were higher in breast-fed infants at 2 months. Alkaline phosphatase, IGF-I, IGFBP-3, and lactic dehydrogenase levels did not differ between the feeding groups. AST levels did not correlate significantly with bilirubin, albumin, alkaline phosphatase, or lactic dehydrogenase values. There was a strong positive association between AST and IGF-I at 2 months (r = 0.47, P = 0.004).


CONCLUSIONS
Cytomegalovirus infection, vitamin K deficiency, and macromolecular forms of AST could be an explanation for a higher AST level among breast-fed infants. However, no other clinical or paraclinical sign of liver disease was seen, all infants were given oral vitamin K, and the AST did not rise to levels comparable to those seen in individuals with macromolecular AST. The authors speculate the most likely explanation of the elevated AST is induction of hepatocytes by factors in human milk. This is supported by the higher albumin levels in breast-fed infants and the positive association between AST and IGF-I.
Department of Paediatrics, Hillerød Hospital, Hillerød, Denmark.
Marianne Hørby
MH
Jørgensen
Peter
P
Ott
Anders
A
Juul
Niels Erik
NE
Skakkebaek
Kim Fleischer
KF
Michaelsen
D000469:Alkaline Phosphatase / Q000097:blood; D001219:Aspartate Aminotransferases / Q000097:blood; D001663:Bilirubin / Q000097:blood; D001942:Breast Feeding / Q000009:adverse effects*; D005500:Follow-Up Studies; D006801:Humans; D006932:Hyperbilirubinemia / Q000209:etiology; D007231:Infant, Newborn; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008099:Liver / Q000737:chemistry* / Q000201:enzymology; D012709:Serum Albumin / Q000032:analysis
D018972:Insulin-Like Growth Factor Binding Protein 3; D012709:Serum Albumin; D007334:Insulin-Like Growth Factor I; D007770:L-Lactate Dehydrogenase; D001219:Aspartate Aminotransferases; D000469:Alkaline Phosphatase; D001663:Bilirubin