High blood cholesterol is a risk factor for coronary heart disease. Reducing both total cholesterol and low-density lipoprotein cholesterol are the primary targets of cholesterol control strategies. Extensive clinical trials have shown that the consumption of a class of compounds found in many plants, called sterols, can reduce both total cholesterol and LDL cholesterol.
Cholesterol and Heart Disease
The link between elevated blood cholesterol levels, especially LDL cholesterol, and the increased risk of coronary heart disease is well established. Elevated levels of total and LDL cholesterol increase the risk of developing atherosclerosis, which results in coronary heart disease. As a weapon in the battle to lower elevated cholesterol, phytosterols, or plant sterols and stanols, are among the dietary options available.
About Sterols and Stanols
Plant sterols and stanols, also called phytosterols, are compounds naturally present in small quantities in the membranes of many plants, including fruits, vegetables, nuts and vegetable oils. More than 60 types are known. According to the Joslin Diabetes Center, plant sterols closely resemble cholesterol in their chemical structure and are processed by the body in the same way. As cholesterol is a component of animal cell membranes, plant sterols play a similar role in their cell membranes.
Plant Sterols and Cholesterol
Plant sterols lower total cholesterol levels by blocking the amount of cholesterol that is absorbed in the digestive tract. When you eat food that contains cholesterol, your intestinal tract absorbs that cholesterol and puts it into the bloodstream. When plant sterols and stanols travel through your digestive tract, they get in the way of dietary cholesterol, preventing it from being absorbed into the bloodstream. In this way, your body absorbs less cholesterol.
Sources of Phytosterols
Whole grains, peanuts, vegetable oils, almonds and brussels sprouts contain plant stanols and sterols. Smaller amounts are found in other vegetables and some fruits. Sterols are becoming increasingly popular as supplements and food additives. It is difficult to get enough plant sterols and stanols from foods, so food companies have begun to add them to margarine, mayonnaise, salad dressings, yogurt, milk, orange juice, cereals and snack bars.
Sterols and Reducing Cholesterol
When added as an ingredient in food at higher levels than found naturally, phytosterols can lower LDL cholesterol. The European Food Information Council points out that intake of 1 to 3g of plant sterols or stanols per day typically results in a 10 percent lowering of LDL cholesterol without affecting HDL cholesterol or triglyceride levels. A 15 percent reduction can be achieved if 2g of phytosterols are combined with a heart-healthy diet low in saturated fat. Based on epidemiological data, it has been estimated that a 10 percent lowering of LDL cholesterol will lower coronary heart disease risk by 20 percent over a lifetime. The National Cholesterol Education Program recommends consuming 2g of plant sterols or stanols every day as part of an overall heart-healthy diet.
References
- Cleveland Clinic: Plant Sterols and Stanols
- The European Food Information Council: Plant Stanols and Sterols Proven to Lower Cholesterol
- "European Heart Journal": Plant Lipids That Lower Serum Cholesterol
- San Jose State University: Moderately Elevated Plant Sterols Associated with Reduced Cardiovascular Risk
- Food & Nutrition Research: Plant Sterols and Stanols as Cholesterol Lowering Agents
- Medscape.com: Phytosterols for Dyslipidemia
