Stearic acid: a possible substitute for trans fatty acids from industrial origin

Trans isomers, contained in partially hydrogenated oils, which are used in the food industry, have been questioned and nowadays trends are heading towards reducing their consumption. The food industry is facing a dilemma, since in order to remove trans fatty acids, hydrogenated fats should be eliminated and replaced by fats rich in saturated fatty acids. Scientific research has shown that saturated fatty acids have negative effects on the lipid profile and its consumption is associated with a higher cardiovascular risk. Therefore it is recommended to avoid their consumption. Nevertheless, not all fatty acids behave in the same way, with stearic acid (18:0) the exception. Stearic acid has a low level of intestinal absorption and its intake does not negatively modify the lipid profile. For this reason, it is considered a neutral fatty acid with regard to cardiovascular health. B-100 apolipoprotein, whose levels determine plasma VLDL and LDL concentration (triglycerides and cholesterol carriers, respectively), is not modified by diets which provide up to 7% of the energy as stearic acid. Markers of cardiovascular risk, such as activation of platelet aggregation factors or C-reactive protein levels, are not modified by diets providing stearic acid, as occurs with other saturated fatty acids. The confirmation of the neutral effect of stearic acid represents a perspective for the development of fats with high contents of this fatty acid to replace hydrogenated fats containing trans isomers. The present review discusses these aspects.