Embodiments of the invention comprise methods of reducing circulating oxidized low density lipoprotein-beta-2-glycoprotein 1 and circulating Myeloperoxidase levels by administering to subjects an effective amount of a dietary oil composition containing 20-90 wt % polyunsaturated fatty acids. Lowering oxidized low density lipoprotein-beta-2-glycoprotein complex and Myeloperoxidase levels may be an effective treatment of atherosclerosis.