Phytosterols

Phytosterols are steroid alcohols present in plants, particularly concentrated in vegetable oils and waxes. Their cholesterol-lowering activity puts them to use in functional foods, including specially formulated margarines and spreads; common examples include sitosterol and stigmasterol. In nutrition, phytosterols compete with cholesterol for absorption in the intestine, reducing blood cholesterol levels. In food technology, they are added as esters to improve fat solubility and product texture, and they occur naturally in nuts, seeds, and unrefined oils. Quality control verifies sterol composition for authenticity of oils, while health claims on enriched products must comply with regulatory requirements for substantiation and labeling.