Cholesterol-lowering foods - 'Functional' for your heart
CNN news, January 18, 1999
ROCHESTER, Minnesota (MAYO CLINIC) -- For years, a "healthy diet" has been largely defined by foods that should be avoided. We've learned to (try to) stay away from potato chips, cookies and virtually everything else that tastes good. Now, the focus may be about to shift toward foods you should work to include in your diet. When major food manufacturers introduce new, specially engineered product lines, their message may be: Eat our cereals, pastas, and even cookies and potato chips as part of your healthful diet.
These new products, enhanced with natural ingredients, are being called "functional foods." According to the American Dietetic Association (ADA), functional foods may provide specific health benefits beyond basic nutrition when consumed as part of a varied diet. Many of the first functional foods to hit the shelves will tout the ability to lower cholesterol, a major contributing factor in cardiovascular disease, the leading cause of death in the United States and other industrialized countries.
However, you don't need to wait until functional foods reach supermarket shelves to make your diet more heart-healthy. "The idea of functional foods came, in part, from understanding which components in natural foods help lower cholesterol, such as soluble fiber, soy protein and plant sterols," says Tu T. Nguyen, M.D., an endocrinologist at Mayo Clinic, Rochester, Minnesota.
A careful review of what's already in your kitchen may reveal a ready cholesterol-fighting menu.
Natural foods fight cholesterol in a number of ways. Although dietary supplements are available for many of these natural substances, they are generally not as effective as the real thing.
Consider increasing your intake of foods containing the following cholesterol-lowering components:
- Soluble fiber We've all heard the phrase, "An apple a day keeps the doctor away." But did you know that adage also holds true for lentils? Apples and lentils are both rich in soluble fiber, which regulates your body's production and elimination of cholesterol. Other good sources of soluble fiber include dried beans, peas, barley, citrus fruits, carrots and oats.
Products containing lots of rolled oats and oat bran were the first to receive approval from the Food and Drug Administration (FDA) to boast on their labels that they may reduce the risk of heart disease when combined with a diet low in saturated fat and cholesterol. However, in order to reap the cholesterol-lowering benefits of oats, you must eat a sizable portion the equivalent of about 3/4 cup of raw oatmeal each day.
- Soy Scientists first suspected a connection between soy and lower cholesterol levels after observing that people in Asian countries where diets contain much more soy than in the United States have significantly lower levels of heart disease than Americans. Experts believe natural soy compounds called isoflavones act like human hormones that regulate cholesterol levels. A 1998 study concluded that regular consumption of soy isoflavones may reduce total cholesterol levels by up to 10 percent.
A minimum of 25 grams of soy protein must be consumed daily in order to reap optimal cholesterol-lowering benefits. Good sources of soy protein include soy milk, tempeh, tofu, and textured soy protein, a main ingredient in many meat substitutes.
- Fish Researchers have found that, in general, the more fish people eat, the less coronary artery disease they have. Fish contain high concentrations of a unique type of fat, omega-3 polyunsaturated fatty acids (PUFAs). In addition to lowering blood fats (triglycerides), studies suggest that omega-3 PUFAs make the blood more slippery and less likely to clot.
A unique study completed in 1997 provided compelling evidence that eating fish can reduce blood cholesterol levels. Researchers studied people in two African villages located 40 miles apart. People from both villages had very similar lifestyles, but their diets were quite different. While one group ate a fish-heavy diet, the other group ate a healthy vegetarian diet consisting largely of rice and maize. Researchers found that the villagers who ate lots of fish had lower cholesterol than the vegetarians. The American Heart Association recommends eating fish two or three times a week.
- Plant sterols Foods containing plentiful plant sterols naturally occurring compounds found in certain plants and vegetable oils also may improve cholesterol levels. "Plant sterols are known to specifically block cholesterol from being absorbed by the intestine," Dr. Nguyen says.
However, very large portions of plant sterols extracted in powder form must be consumed in order to benefit. Functional foods may soon make heart-healthy consumption of plant sterols more feasible.
Functional foods have captured international attention recently thanks to a product marketed as Benecol. Manufactured in Finland, Benecol is a margarine made with a refined form of plant sterol called stanol ester, which is efficient in lowering cholesterol. A study published in the New England Journal of Medicine in 1995 indicated that regular, long-term use of Benecol may lower total cholesterol levels by up to 10 percent. FDA approval for sales of Benecol in the United States is pending.
Several other companies also are set to introduce functional foods. One major manufacturer will present a cholesterol-lowering margarine similar to Benecol, but enriched with a different form of plant sterol. This product has not been studied as extensively as Benecol.
Plant sterols and stanols are not the only ingredients being used in functional foods. Currently, the other major components are soluble fibers from oats and from a plant seed called psyllium (SILL-ee-um). Psyllium is a primary ingredient in many laxatives. New functional foods may offer tastier ways to consume this fiber.
A number of new products enhanced with oats and psyllium will soon be arriving in your supermarket. These functional foods will include dried pasta, frozen entrees, bread, cereal, baked potato crisps and cookies. Multiple servings of these foods must be consumed each day in order to potentially lower cholesterol.
Many more functional foods geared toward lowering cholesterol are anticipated. In order to provide benefits, these foods must be combined with a diet low in saturated fat and cholesterol, as well as regular physical activity.
"Lowering cholesterol with functional foods doesn't mean you can stop exercising, increase your calorie intake, or continue smoking," Dr. Nguyen says. "It is not a silver bullet. The message is, everything in moderation."