OLIVE OILS AND HEALTH 52 LDL size. On the other hand, trans fatty acids increase plasma cholesterol, triglycerides, and lipoprotein (a), and decrease HDL cholesterol concentrations. A positive linear relationship occurs between trans fatty acid consumption and plasma cholesterol, particularly LDL. Figure 2.4 shows, for the same fat amount, a higher increase in cholesterol levels after trans fatty acid (circles) consumption than after saturated fat (squares). Thus, trans fatty acids are even more atherogenic than saturated ones. Besides promoting an atherogenic lipid profile, trans fatty acids negatively affect endothelial factors and the inflammatory response, thus contributing to cardiovascular disease development. Based on the impact on the plasma lipid profile of trans fatty acid consumption, Mozzafarian et al., estimated that a 50% reduction (from 2% to 1% of total dietary energy) of trans fatty acids would be associated with a 3% decrease in cardiovascular events. In addition, the removal of trans fatty acids from the diet would be associated with a 6% reduction in cardiovascular events. If the substitution of 2% dietary trans fatty acids is with cis unsaturated fats, the associated decrease in cardiovascular events would be 12-22%. Such figures may even improve if the substitution is carried out with extra virgin olive oil which contains antioxidants and polyphenols. Figure 2.4. Effect of trans fatty acids on the cholesterol LDL/HDL ratio. Effect of trans fatty acid (circles) and saturated fat (squares) consumption on human plasma cholesterol LDL/HDL ratio in several studies. From Ascherio A, Katan MB, Zock PL, Stampfer MJ, Willett WC. Trans fatty acids and coronary heart disease. N Engl J Med 1999:340(25); 1994-1998. Trans Saturated fat Percentage of energy from fat L2 L2 L2 Lichtenstein ** ** * ** ** Nestel L2 Judd ‘94 Judd ‘94 Sundram Zock Judd ‘98 Aro Mensink Sundram LDL/HDL ratio • o < 0.05 * o < 0.005 ** o < 0.0001 1.2 1.0 0.8 0.6 0.4 0.2 LDL/HDL ratio • o< 0.05 , o< 0.005 " o< 0.0001 Lichtensteinl L2 • L2 e Zoc·~• Aro • • J~d ----· '94 -• --- ----•--- /1 • O.O 1 Sundram -o.2 l-....,..----:i:---:r--~~~~5r--~6~-17--rª--;9~- 11 º o 2 3 • •
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