Changes in concentrations of blood lead, cholesterol, tnacylglycerols, GOT and GPT enzymes, phosphorus, proteins, plasma calcium and magnesium, and erythrocyte magnesium were studied for 25 weeks in 4 groups of 6 rabbits each receiving different diets: I (controls), II (water with 9.66 µmol/l of lead), III (atherogenic) and IV (atherogenic + 9.66 µmol/l of lead). Differences observed, with respect to the diets, for lead, cholesterol, enzymes, proteins and erythrocyte magnesium were evident from the 42nd day on. Low lead doses raised the levels of cholesterol and tnacylglycerols in group II, whereas triacylglycerols were lower in the plasma of group IV in comparison with group III and were accumulated in the aorta. The elevation of enzymes in groups III and IV indicated heart and liver dysfunctions. There was a significant drop in erythrocyte magnesium in groups III and IV, which was especially marked in the latter group, with an interaction between the two diet