Lowering of Plasma Cholesterol and Enhanced Sterol Excretion with the Consumption of Polyunsaturated Ruminant Fats

Abstract

A substantial increase in the linoleic acid content of the milk and meat fat of cattle can be achieved if the ruminal hydrogenation of seed-oil linoleic acid is prevented, thereby increasing the ratio of polyunsaturated to saturated fatty acids in cattle meat and milk 10 times. In a comparison of these and of conventional ruminant fats a significant reduction (10 per cent) in plasma cholesterol was observed in five of six subjects on such diets over periods of three to four weeks. In five subjects, the total excretion of sterols increased by an average of 18 per cent when polyunsaturated ruminant fats were eaten. The significant increase in both mean neutral sterol and bile acid excretion coincided with the fall in plasma cholesterol. Thus, increasing unsaturated fats in the diet of cattle lowered plasma cholesterol of subjects on diets containing food products from such cattle.