BACKGROUND Epidemiological trials provided evidence that the cholesterol concentration in lipoproteins B, i.e. VDL, IDL and LDL, correlate significantly with the incidence of ischaemic heart disease (IHD). The objective of the present study was to assess how the fatty acid composition in plasma phosphatidyl choline affects the total and LDL cholesterol, triglyceride and apolipoprotein B concentrations in subjects with primary hyperlipoproteinaemia and dyslipidaemia. RESULTS In a group of 142 subjects with primary hyperlipoproteinaemia and dyslipidaemia the concentrations of plasma lipids, lipoproteins apolipoproteins and fatty acids in plasma phosphatidyl choline (PC) were assessed. The authors provided evidence by discriminant analysis where the dependent variables were the lower quintiles (Q1 + Q2) and the upper quintiles (Q4 + Q5) of concentrations of total cholesterol, triglycerides, LDL-cholesterol and apolipoprotein B and the independent variables were FA concentrations in plasma PC, that the total cholesterol concentration was inversely associated with the concentration of docosahexaenic acid (22:6n-3). The concentration of LDL-cholesterol correlated inversely with the concentration of palmitoleic acid (16:1n-7). Triglyceridaemia was inversely associated with the linoleic acid concentration (18:2n-6). The concentration of apolipoprotein B correlated positively with myristic acid (14:0) and negatively with concentrations of oleic acid (18:1n-9) and linoleic acid (18:2n-6). CONCLUSIONS The submitted results indicate that the fatty acid concentrations of PC in plasma are significantly and markedly correlated with concentrations of total cholesterol, triglycerides, LDL-cholesterol and apolipoprotein B. It is possible that atherogenic lipoproteins may be favourably influenced not only by the amount of fat but also by a suitable fatty acid composition.