Fytosterolit

Fytosterolit, commonly called phytosterols, are a group of plant-derived sterols and stanols that resemble cholesterol in structure. The most common compounds are beta-sitosterol, campesterol, stigmasterol, and sitostanol. They occur in many plant foods such as vegetable oils, nuts, seeds, whole grains, fruits, and vegetables, and they can also be added to fortified foods and dietary supplements.

In the small intestine, phytosterols compete with cholesterol for incorporation into micelles, reducing the absorption of dietary and biliary cholesterol. This leads to lower levels of circulating LDL cholesterol and a modest impact on total cholesterol.

Evidence from randomized trials shows that daily intakes typically around 1–3 g of phytosterols/stanols can lower LDL cholesterol by about 5–15%, depending on dose and baseline levels. Regulatory agencies in many regions permit health claims that plant sterols contribute to the maintenance of normal blood cholesterol levels, usually with an effective intake near 0.8 g per day or higher.

Phytosterols are widely consumed through fortified foods such as spreads, yogurt, and beverages, as well as dietary supplements. They are generally safe for adults, but very high intakes may reduce the absorption of fat-soluble vitamins and may cause mild gastrointestinal symptoms. People with sitosterolemia, a rare inherited condition, should avoid high phytosterol intake. Those taking cholesterol-lowering medications should consult a clinician about possible additive effects.