sn-2 Hypothesis: a Review of the Effects of Palm Oil on Blood Lipid Levels

Saturated fats are commonly claimed to raise human blood cholesterols and contribute to cardiovascular disease. Previous literature data were highlighted that although palm oil is 50% saturated, it does not behave like a saturated fat. Human trials were conducted to compare the effects on serum cholesterol levels given by palm olein and monounsaturated oils. It was postulated that saturation/unsaturation of the fatty acids situated at sn-2 positions of triglycerides in the fat molecules determine the induced blood lipid levels but not the overall saturation of oils. The results showed that the lipid parameters (LDL and HDL) effects induced by these oils are similar with no significant differences. This study provides concrete evidence that the unsaturation levels of these oils at sn-2 position of TG are similar (90-100%) which are claimed to be responsible for the lipid parameters. In conclusion, the public negative perception on believing that the overall saturation of oils is detrimental to health should be corrected because in fact the unsaturation at sn-2 positions of the saturated vegetable fat such as palm olein and cocoa butter make them behave like mono-unsaturated oils, unlike saturated animal fats that possess a high content of saturated fatty acids at sn-2 position.