Plant sterols and stanols are a group of substances made in plants that resemble cholesterol. Plant sterols and stanols have a structure that is very similar to that of cholesterol. The difference between stanols and sterols is that stanols are saturated and sterols are not. Sterols have functions in plants similar to that of cholesterol in animals. Research has shown that plant sterols and stanols help lower cholesterol. Cholesterol is a waxy substance your body uses to protect nerves, make cell tissues, and produce hormones. The liver makes cholesterol. Your body also gets cholesterol directly from certain foods (such as eggs, meats, and dairy products). There are 2 types of cholesterol:
High levels of LDL cholesterol may damage your arteries and can be related to heart disease. A high level of HDL cholesterol, on the other hand, is beneficial. It helps protect your arteries and prevent fatty deposits that can clog arteries.
Sterols and stanols are found in the highest amounts in foods like vegetable oils, nuts, and seeds. Plant sterols and stanols are most commonly used for lowering cholesterol levels. They help reduce cholesterol levels by limiting the amount of cholesterol that is able to enter the body. Some plant sterols might also reduce how much cholesterol is made in the body. On a molecular level, sterols and stanols look a lot like cholesterol. So when they travel through your digestive tract, they get in the way. They can prevent real cholesterol from being absorbed into your bloodstream. Instead of clogging up your arteries, the cholesterol just goes out with the waste. Plant sterols and stanols are used in people that have an inherited tendency towards high cholesterol (familial hypercholesterolemia) and high cholesterol in general. When taken in people who are also following a low-fat or cholesterol-lowering diet, plant sterols and stanols can reduce total and LDL cholesterol more than the diet alone. They do NOT decrease triglycerides or increase HDL. Taking plant sterols and stanols lowers total and LDL cholesterol levels by about 3% to 15% in people with high cholesterol who are following a cholesterol-lowering diet. When added to a cholesterol-lowering prescription medication, such as a statin, plant sterols and stanols reduce total cholesterol by an additional 12-22 mg/dL and LDL cholesterol by 11-16 mg/dL.
Plant sterols and stanols can be incorporated in margarines, dairy products, and breads and cereals, or taken in pill form. The FDA has given these products the status of a "health claim." This means that experts widely agree on the cholesterol-lowering benefits of stanols and sterols. It also allows manufacturers to advertise the heart-healthy benefit of these produces on their labels. Research suggests 2-3 grams daily lowers cholesterol the most. In adults, 1.6-1.8 grams of plant sterols per day have been used.