Selected parameters of lipid metabolism were studied in a group of 76 children aged 12-13 years. The children were divided into 4 subgroups according to the duration of neonatal nutrition (no breast feeding, breast feeding for 3, 6 or more than 6 months). We studied the concentration of total serum cholesterol, its distribution into lipoprotein fractions, the concentration of serum triacylglycerols and apolipoproteins A1 (Apo A1) and B (Apo B). Atherogenic indexes were calculated from the data obtained. The highest cholesterol levels (5.20+/-0.15 mmol x l(-1)) were found in children who had been breast-fed for more than 6 months, while the highest concentrations of Apo B (0.80+/-0.07 g x l(-1)) and Apo A1 (1.76+/-0.06 g x l(-1)) and the highest Apo B/Apo A1 ratio (0.45+/-0.04) were found in children with the shortest period of breast-feeding. No significant sex-related differences in total, VLDL, LDL, HDL cholesterol, triacylglycerols and apolipoproteins were observed.