Lipid metabolism and the blood lipid peroxidation system were examined in 56 military males living in rather similar conditions. The parameters in question were compared in the following groups: (1) control subjects, including healthy individuals without a family history of atherosclerotic vascular abnormalities; (2) healthy subjects with a family history of atherosclerosis; (3) patients with coronary heart diseases. There were significant differences only in single cases between the groups. The application of a system of grids setting upright the distribution curves for the parameters under study proved to be effective in finding significant differences between the groups, showing the value of the hereditary factors in the development of atherogenic lipid changes.