Technical Abstract: Cardiovascular disease is still the main cause of death in the U.S. High plasma cholesterol, especially low density lipoprotein (LDL) cholesterol, and high ratios of LDL to high density lipoprotein (HDL) cholesterol are risk factors for cardiovascular disease. 51.9% of Americans have cholesterol levels of 200 mg/dL or higher. Plant stanol esters have been shown to be effective in reducing plasma cholesterol. Other phytosterols such as oryzanol, a mixture of ferulate esters from rice bran, and tomatine, a glycoalklaoid in green tomatoes, have also shown cholesterol-reducing properties in test animals. The investigation and use of plant phytosterols is facilitated by animal models that respond to phytosterols, as well as other known cholesterol lowering agents. The hypercholesterolemic LDL hamster is used to efficiently screen phytosterols for plasma cholesterol lowering properties. Hypercholesteremia is induced by saturated fat and fish oil in the diet. Dietary cholesterol intake is similar to humans, 0.025-0.05%, and results in rapid LDL hypercholesteremia. Known plasma cholesterol reducing agents such as cholestyramine, soluble dietary fiber, stanol esters, oryzanol and tomatine reduce total and LDL cholesterol. Gas chromatograph/mass spectrometry indicates that tomatine binds cholesterol, but fiber and cholestyramine excrete bile acids. Prolonged feeding of the hypercholesterolemic diet results in aortic fatty streak formation which can be retarded by the antioxidants alpha tocopherol or catechin.