Fatty livers, with some increase in liver cholesterol, were produced by feeding rabbits a diet containing 0.43% cholesterol; 0.22% cholesterol produced no changes in liver fat. Both levels of cholesterol produced marked atheromatous lesions, and a striking increase in the cholesterol content of the aorta and blood. Three hundred mg of choline hydrochloride daily failed to counter-act the effect of cholesterol in the blood, liver or aorta.