Sterol esters are a heterogeneous group of chemical compounds.
They are created when the hydroxyl group of a sterol and a fatty acid undergo an esterification reaction.
[1] Plant sterol esters have been shown to reduce the level of low-density lipoprotein (LDL) cholesterol in blood when ingested.
They are added to certain oil-containing products like margarine, milk, or yogurt to make functional foods for controlling cholesterol levels.
Studies have indicated that consumption of about 2 grams per day of phytosterol esters provides a reduction in LDL cholesterol of around 10%.