Having high cholesterol levels predisposes you to developing a number of different health problems including a heart attack or stroke. Sitosterol is a member of the plant sterol family of compounds, which are substances that are sometimes used to lower blood cholesterol levels. Your doctor may recommend plant sterols, such as sitosterol, if you have high cholesterol.
Understanding Plant Sterols
Plant sterols are substances found in the cell membranes of plants. These compounds are essentially the plant version of cholesterol and help keep the cell membranes fluid. This allows proteins and other substances in the plant cell membrane to move around to other parts of the cell. Although sitosterol and other plant sterols are similar to cholesterol in the human body, your body cannot use them as a replacement for cholesterol.
Effects on Cholesterol
One of the main reasons that people take sitosterol is to lower their cholesterol levels. Plant sterols can reduce your blood cholesterol levels in a dose-dependent fashion, although doses above 2 g do not have any additional affect over 2 g per day. Drugs.com notes that those taking 2 g of plant sterols per day experience an average drop of 21 mg/dL for LDL levels if you are between 50 and 59 years old, 17 mg/dL if you are between 40 and 49 and 13 mg/dL if you are between 30 and 39.
Mechanism
The way that sitosterol affects your blood cholesterol levels has to do with cholesterol absorption. Sitosterol is similar in structure to human cholesterol, which means that it can block the proteins in the intestines, which transport cholesterol from your diet into your bloodstream. By binding to and blocking these proteins, sitosterol inhibits cholesterol absorption, which lowers your blood cholesterol levels.
Sources
Sitosterol and other sterols are found in many different plant-based foods, but are usually only present in small quantities. To reap the benefits of these beneficial chemicals, you may need to consume foods supplemented with sitosterol and other sterols. These include some brands of tub margarine, other dairy products and certain types of orange juice. Sitosterol is also available as a supplement; the recommended dosage depends on the product that you take.
Considerations
Products that contain plant sterols may be more expensive than the same product without the sterols, Pennsylvania State University states. The benefits of consuming plant sterols also end when you stop consuming them on a regular basis. You need to consume 2 to 3 servings of foods fortified with sterols in order for them to be effective, and margarines and other foods with sterols may not be slightly less flavorful than similar products.
