Type of milk feeding affects hematological parameters and serum lipid profile in Japanese infants.

Background:  Type and volume of infant feeding determines infant growth, hematological parameters, and serum lipids. Methods:  Study subjects consisted of 103 infants who were born vaginally at term, with birthweight >2200 g. Milk feeding amount, type, and anthropometry were measured at 1 and 6 months. Hematological tests and serum lipid profile were assessed at 1 and 6 months. Thirty-four infants were breast-fed and 36 were formula-fed at 6 months. Results:  Breast-fed infants demonstrated similar growth patterns compared with partially breast-fed or formula-fed infants, despite the lower milk intake. Infants with higher breast milk intake at 6 months, however, tended to have lower hemoglobin levels. In contrast, higher formula intake at 6 months was related to lower serum total cholesterol. Conclusions:  Japanese breast-fed infants were more likely to be anemic at 6 months, while formula-fed infants were likely to have low serum lipid levels. Iron-fortified infant foods may be useful to prevent anemia in breast-fed infants. Fat quality of infant formulas should be improved to enhance lipid status of formula-fed infants.