betasitosterol

Beta-sitosterol is a plant-derived sterol, a type of phytosterol closely related to cholesterol. It is one of the most abundant phytosterols in the human diet and is commonly found in fruits, vegetables, nuts, seeds, and vegetable oils.

Natural occurrence: Major dietary sources include vegetable oils (soybean, corn, sunflower, olive), nuts and seeds, avocados, and legumes. Typical daily intake varies with diet but can range from a few tens to several hundred milligrams.

Biological role and mechanism: In the human gut, beta-sitosterol competes with cholesterol for incorporation into micelles, reducing intestinal absorption of cholesterol and producing modest reductions in LDL cholesterol in some individuals.

Uses and regulation: Beta-sitosterol is used in dietary supplements and in some traditional medicines. It is marketed for cholesterol management and, in some cases, as an ingredient claimed to alleviate symptoms of benign prostatic hyperplasia (BPH). Regulatory status varies by country; it is not approved as a drug by major agencies in many places.

Safety and side effects: Generally well tolerated; high intakes may cause gastrointestinal symptoms. Rare hereditary disorders like phytosterolemia cause accumulation of plant sterols and increased risk of atherosclerosis.

Chemistry: Beta-sitosterol has the chemical formula C29H50O and a sterol structure similar to cholesterol, with an additional ethyl group at the side chain.