The effect of bakery compressed yeasts in the amounts of 6 and 12 g/100 g of the ration was studied in rats. It was revealed that 12 g of yeasts per 100 g of the atherogenic ration produced a hypocholesterolemic effect. A negative effect of this amount of the yeasts was manifest in the slow growth of the rats' body mass and in an increased ratio of the kidney/body mass. The yeasts amounts used did not protect the test animals from the kidney infiltration with lipids and cholesterol; 12 g of yeasts per 100 g of the ration promoted elevation of sialic acid content in the blood plasma. Morphologic changes were observed only in the aortal wall, they were characteristic of the prelipid stage of atherosclerosis and did not depend on the yeasts amount.