Our aim was to investigate (1) whether different campestanol/sitostanol mixtures in margarine differ in reducing serum cholesterol, and (2) whether sitostanol ester in butter decreases serum cholesterol and alters cholesterol absorption and metabolism. Twenty-three postmenopausal women replaced 25 g dietary fat with (1) sitostanol ester-rich (campestanol to sitostanol ratio 1:11) and (2) campestanol ester-rich (campestanol to sitostanol ratio 1:2) rapeseed oil margarine, (3) butter, and (4) sitostanol ester-rich (campestanol to sitostanol ratio 1:13) butter. The respective scheduled stanol intake was 3.18, 3.16, and 2.43 g/d. The 6-week margarine periods and, after an 8-week washout, 5-week butter periods were double-blind and in random order. Serum cholesterol precursor sterols (indicators of cholesterol synthesis) and plant sterols (indicators of cholesterol absorption) were quantified with gas-liquid chromatography (GLC). Low-density lipoprotein (LDL) cholesterol was reduced by 8% and 10% with the sitostanol and campestanol ester-rich margarines versus baseline (P < .05 for both) and high-density lipoprotein (HDL) cholesterol was increased by 6% and 5% (P < .05), so the LDL/HDL cholesterol ratio was reduced by 15% (P < .05 for both). Sitostanol ester-rich butter decreased LDL cholesterol 12% and the LDL/HDL cholesterol ratio 11% (P < .05 for both) versus the butter period. The serum proportions of plant sterols and cholestanol were similarly reduced and those of cholesterol precursor sterols were similarly increased during all periods (P < .05 for all). Serum proportions of sitostanol and campestanol were slightly increased, indicating that their absorption related to their dietary intake. During all stanol interventions, serum vitamin D and retinol concentrations and alpha-tocopherol to cholesterol ratios were unchanged, whereas those of alpha- and beta-carotenes were significantly reduced. We conclude that varying the campestanol to sitostanol ratio from 1:13 to 1:2 in margarine and in butter similarly decreased cholesterol absorption, LDL cholesterol, and the LDL/HDL cholesterol ratio such that the serum lipids became less atherogenic.