In just about every study purporting to show that people or animals lowered their LDL bad cholesterol levels after starting to use olive oil, the subjects used olive oil in place of other dietary fats, often saturated fats like butter, coconut oil, or lard. Well, of course LDL cholesterol is going to be lower when olive oil replaces butter. The total amount of saturated fat and/or cholesterol in the diet takes a tumble when butter is removed.