[Phytosterols as a functional food]

Abstract

Many dietary recommendations which try to lower the concentration of total, respectively LDL cholesterol, force us to look back to vegetable-based diet. The plants synthesize many compounds similar to cholesterol, called phytosterols and phytostanols, and these sterols are consumed in average Western diet in amounts ranging from 200 to 500 mg/day. Phytosterols and phytostanols share the mechanisms of absorption with cholesterol molecule and influence the cholesterol metabolism inside the enterocytes. Both types of phytoanalogs of cholesterol were proven to be potent cholesterol-reducing agents; their daily intake about 2 g/day reduces the LDL-cholesterol by 15%. The underlying mechanisms involve the prevention of cholesterol absorption from the gut lumen and slower esterification rate of phytosterols (phytostanols) inside the enterocytes. In contrary to phytostanols, phytosterols are absorbed with yet-to-be-considered efficiency, appearing in plasma with concentrations reaching as much as 1% that of total cholesterol. The hypocholesterolemic effect of phytosterols (phytostanols) can be further supported with the combination of dietary (n-3 polyunsaturated fatty acids, fibre) regimen as well as pharmacological intervention (statins). To conclude, plant sterols represent safe dietary approach to lowering of plasma total cholesterol with the attention paid to the intake of lipid soluble vitamins.