Growth of Japanese breast-fed and bottle-fed infants from birth to 20 months.

Longitudinal data for weight and length from birth to the 20th month of age obtained from 318 healthy infants were analysed in relation to type of feeding during infancy (breast- or bottle-fed). Differences in the growth patterns of infants according to the type of feeding were confirmed, breast-fed infants tending to be lighter in weight between 6 and 20 months of age than bottle- or mixed-fed infants. However, our analyses of the infants' growth patterns suggest that the differences in mean weight between breast- and bottle-fed infants may be due at least in part to overfeeding of bottle-fed infants. Thus, it is advisable that the standard growth curve for breast-fed infants be based on observations of the growth of a large number of infants who are fed on breast milk only.