Comparison of Low and High Phytosterol Diets With Respect to Cholesterol Metabolism

Inclusion Criteria: * Male or female of any race or ethnicity between 18 to 80 years of age, inclusive; * Body mass index between 20-35 kg/m2; * LDL-cholesterol between 100-189 mg/dL based on the average of duplicate screening measures. If the two LDL-C levels differ by more than 30 mg/dL, a third test will be scheduled with all three results averaged; * Free of chronic disease; * Willing to eat only the foods that are provided by the Center during the diet periods; * Willing to consume no more than 1 alcoholic drink per day. * Willing to abstain from the consumption of alcohol for 48-hours prior to blood draw days; * Willing to drink no more than 5 cups of caffeine-containing beverages a day. Exclusion Criteria: * Age \< 18 or \> 80 years; * Based on duplicate screening laboratory values: 1) LDL-C \> or = 190 mg/dL; 2) TG \> or = 250 mg/dL; 3) blood pressure \> or = 160 mm Hg systolic or 95 mm Hg diastolic; * Documented presence of atherosclerotic disease; * Diabetes mellitus; * Renal, hepatic, endocrine, gastrointestinal, hematological or other systemic disease; * Body mass index \> 35; * For women, pregnancy, breast feeding or postpartum \< 6 months; * For women, peri-menopausal; * History of drug or alcohol abuse; * History of depression or mental illness requiring treatment or medication within the last 6 months; * Multiple food allergies or significant food preferences or restrictions that would interfere with diet adherence; * Chronic use of over-the-counter medication which would interfere with study endpoints including laxatives and antacids; * Lifestyle or schedule incompatible with the study protocol; * Planned continued use of dietary supplements through the study trial; * Taking any lipid-lowering, or other medications known to affect blood cholesterol