The effect of soy protein on serum lipid profile and some lipid metabolizing enzymes in rats fed with cholesterol diets was examined in this study. Rats were subjected to feeding trial over a period of sixweeks on formulated diets containing: 20% soy protein with 0% cholesterol (group A), 20% soy protein with 5% cholesterol (group B), 20% soy protein with 10% cholesterol (group C), 0% soy protein with 20% cholesterol (group D), and 5% soy protein with 20% cholesterol (group E). Serum total, VLDL, LDL, and HDL-cholesterol and triglyceride concentrations were found to be reduced significantly in Groups B and C when compared with Groups D and E (p 0.05). Groups D and E showed significant increased levels (p < 0.01) when compared to other groups. Lipoprotein lipase (LPL), lecithin:cholesterol acyl transferase (LCAT), and triglyceride lipase (TGL) activities were found to be significantly reduced (p< 0.05) in groups B and C when compared with groups D and E. Though groups B, C, D, and E rats all showed significant elevation (p < 0.05) in the enzyme activities when compared to the control
