ROLE OF INFANT-FEEDING PRACTICE, SEX, AND AGE ON FATNESS AND SUBCUTANEOUS FAT DISTRIBUTION IN INFANCY - LONGITUDINAL ANALYSIS OF MULTIPLE SKINFOLD MEASUREMENTS

The aim of this study was to determine whether subcutaneous fatness an d fat distribution differ on the basis of feeding practice and sex dur ing the first 6 months of life. Longitudinal principal components anal ysis (PCA) was done on skinfolds measured at five sites in 45 breast-f ed and 41 formula-fed infants. The first component represented fatness , the second component change in fatness, and the third component uppe r body/lower body fat distribution. Analysis of the components indicat ed that fatness and the proportion of lower body fat were greater in b reast-fed than in formula-fed infants; however, when race was included as a predictor, the differences in lower body fat did not persist. Th e interpretation of components and the group differences were confirme d by repeated measures analysis of variance (ANOVA) on the sum of skin folds (fatness) or simple skinfold ratios (fat distribution). Group di fferences for fatness and upper body/lower body fat persisted when rac e was included as a predictor. Longitudinal PCA of another indicator, the Rohrer index, suggested that fatness was greater in formula-fed th an breast-fed infants. Collectively, these findings suggest that formu la-fed infants have less subcutaneous fat than breast-fed infants; how ever, formula-fed infants may have either more internal fat or more le an body mass. (C) 1997 Wiley-Liss, Inc.