Plant sterols and stanols -- also called phytosterols -- are compounds present in small quantities in many plant foods, including fruits, vegetables, and vegetable oils. Plant sterols and stanols can be found in a variety of enriched products, including certain margarines, orange juice and orange drinks, salad dressings, and snack bars, as well as in supplements.
When added as an ingredient in food at higher levels than found naturally, phytosterols can lower LDL cholesterol. Studies have shown that consuming 2 to 3 g a day of plant sterol or stanol esters can lower LDL cholesterol by 6 to 15 percent -- often within weeks -- without affecting HDL-cholesterol or triglyceride levels. This is possible because these compounds block the absorption of cholesterol from the digestive tract. Consuming more than this amount, however, won't lower cholesterol any further. It's important to note that the cholesterol-lowering effect of plant sterols and stanols is in addition to statins; however, if a cholesterol absorption inhibitor, such as ezetimibe, is used, these supplements are probably of limited benefit.
The Food and Drug Administration has allowed manufacturers of products enriched with a specified amount of plant sterols or stanols (at least 0.65 g of plant sterol esters or at least 1.7 g of plant stanol esters per serving) to claim effectiveness in lowering blood cholesterol when eaten twice a day as part of a diet low in saturated fat and cholesterol.
Consuming more fiber can also help lower cholesterol. Read on to learn how psyllium, a natural, soluble fiber, can help reduce total cholesterol.