Dietary fat and experimental atherosclerosis

This paper reviews studies relating to the effects of fat unsaturation and fatty acid composition on the development of experimental atherosclerosis in rabbits. The results derived from the feeding of various fats are similar whether one feeds cholesterol or an atherogenic, cholesterol-free semipurified diet. In general, the severity of atherosclerosis is inversely related to the level of fat unsaturation. Two exceptions are cocoa butter which is much less atherogenic than expected, most probably due to its high content of stearic acid, and peanut oil, while relatively unsaturated, is surprisingly atherogenic for rats, rabbits and monkeys. This latter effect is not related to the level (6%) of long-chain saturated fatty acids (arachidic, behenic, lignoceric) present in peanut oil, but rather to its triglyceride structure. Randomization of peanut oil, which modifies its triglyceride structure, significantly reduces its atherogenicity.