Looking for a relation between serum leptin concentration and body composition parameters in healthy term infants in the first 6 months of life

We carried out a cross-sectional study of 115 healthy infants, younger than 6 months old, exclusively breast-fed or formulated, to investigate correlations between circulating leptin concentrations and body composition measurements. Serum leptin was evaluated with radioimmunoassay, and body composition with bioelectrical impedance analysis. Multiple regression analysis showed a relationship between serum leptin and body mass index in the entire study population (P = 0.042). There was a significant negative relationship between serum leptin and phase angle (P = 0.006) in formula-fed infants. Serum leptin was positively related to subscapular skinfold thickness (P = 0.055) and negatively to reactance (P = 0.057) only in formula-fed infants, although the differences were just below significance. Serum leptin concentration was higher in breast-fed infants (P = 0.002), and was. not correlated with body composition parameters. This study indicates that there is a relation between leptin and infant body composition in the first months of life, although the link needs to be explored further.