MONOUNSATURATED OILS DO NOT ALL HAVE THE SAME EFFECT ON PLASMA-CHOLESTEROL

Evidence assembled here indicates that when olive oil forms a major pa rt of dietary fat in controlled human experiments, total and LDL-chole sterols are somewhat higher than when the same amount of fat is one of the modem predominantly monounsaturated oils: low erucic rapeseed or high oleic sunflower oil. Oils rich in monounsaturated fatty acids thu s do not all have the same effect on plasma cholesterol. This phenomen on is explicable by consideration of the content of other fatty acids and the non-saponifiable fractions of the different monounsaturated oi ls. It helps to explain the discrepancy that has existed between the c lassic experiments (using olive oil), which found monounsaturated oils 'neutral', and some of the more recent experiments which found them m ore cholesterol-lowering than carbohydrates. Four published meta-analy ses are reviewed. The three which included most of the published exper iments show that monounsaturated fatty acids (MUFA) have less plasma c holesterol-lowering effect than polyunsaturated fatty acids.