Functional foods are defined as any modified food that may provide a health benefit beyond the traditional nutrients it contains. Two new margarines that have hit the grocery store shelves contain unique added ingredients that assist in lowering cholesterol levels. Research has shown that naturally occurring plant sterols and stanols lower cholesterol if eaten in therapeutic amounts. These naturally occurring plant compounds reduce the absorption of dietary and biliary cholesterol in the intestinal tract, similar to the action of oat bran, pysllium seed and other sequestrants.

Benecol, a cholesterol-lowering margarine made by McNeil Consumer Products, has been used in Finland since 1995, where a study revealed that LDL cholesterol was reduced by 20 percent in postmenopausal women. The FDA delayed the introducing the margarine into the United States until resolving whether the new margarine was a dietary supplement or a food product. Now approved, Benecol can be found in light or regular versions. It contains plant stenol esters from pine trees. This margarine spread can be used to cook, bake and fry. The company plans other products with this cholesterol-lowering ingredient.

Take Control, by the makers of Promise (Lipton) is a low-fat spread that contains plant sterols from soybean extract. Studies indicate that products containing this soybean extract may lower LDL-cholesterol by 7 to 10 percent. The ingredient inhibits the absorption of cholesterol in the small intestine. The spread is not recommended for baking or frying.

A third product not available yet, called Phytrol, is developed by Forbes Medictech. It contains a mixture of phytosterols and phytostanols and is now in clinical trials.

If you have high cholesterol, how do you incorporate these functional margarines into your diet? Benecol recommends three servings a day, and it takes two weeks for the benefit to be measurable. Each serving is an individual packet, and at 45 calories or 5 grams of fat each, you would be adding 135 calories a day, or 15 fat grams a day, to your diet. If you add 100 calories a day to your diet, in a year you will gain 10 pounds. To avoid weight gain, the margarine should replace other calories in your diet. If you limit your fat intake to 40 grams a day, 15 grams are committed to this margarine. If you try to include a teaspoon or two of olive oil in your diet, then you are left with a meager 20 grams of fat from other food. Dietitians are curious if there is a beneficial effect if the three-a-day dose is not maintained.

Take Control recommends one to two servings a day, and at 50 calories a tablespoon and 6 grams of fat, you need 35 calories less than Benecol to get a cholesterol-lowering effect.

If one eats more, will the cholesterol-lowering effect be greater than predicted? Are there any digestive side effects, or vitamin absorption concerns?

Functional margarines are another possible dietary change to add to all the other recommendations for lowering cholesterol — none of which would stand alone in the treatment plan. These new margarines do not contain trans fatty acids, a bonus over the selection of other margarines on the market. Although they are pricey, perhaps functional margarines should be reserved for use by family members with high cholesterol. Treat the use of these margarines like a prescription medication, following the dosage carefully for maximum results. Be sure to figure the fat into your total fat intake to avoid weight gain and keep below the 30 percent total dietary fat recommendation of the American Heart Association.