First, there were healthy "margarine-like" spreads. Then came orange juice, followed by yogurt, granola bars, "rice milk," cheese, and now, chocolate bars.

A growing number of popular foods are being fortified with natural plant substances that lower so-called bad cholesterol -- low density lipoprotein (LDL) -- by 10 to 15 percent.

"Major sectors of the food arena are seeing these materials being added," said Peter J.H. Jones, professor of dietetics and human nutrition at McGill University in Montreal, who has received food industry funding for his research. "The efficacy is indisputable. . . . The sky's the limit because you can put this stuff into anything. It has no taste, no after-odor, no negative 'mouth feel.' "

Combine the plant additives with some other dietary changes -- reduce fried food and products with trans fat, eat more fiber and beans, some nuts, a little soy and consume fewer egg yolks and other cholesterol-rich food -- "and you can get a total reduction in LDL of 25 percent," said Jones. That approaches what prescription statin drugs can do. Plus, there's evidence that these foods can help reduce the dose of statins needed for those who can't get their blood cholesterol levels lower with diet changes alone.

Known as sterols and stanols, these substances are the plant world's version of cholesterol, but they don't add to heart disease risk. They lower LDL levels because they are absorbed preferentially in the intestine, edging out other cholesterol, which then gets eliminated from the body. In 2001, the National Heart, Lung, and Blood Institute recommended that people with elevated blood cholesterol levels add foods fortified with sterols and stanols to help cut their LDL levels.

As promising as these substances appear to be, they don't work for everyone. Up to 20 percent of people with high blood cholesterol levels who eat significant amounts of sterols and stanols fail to show improvements, for reasons still not understood.

Studies also show that it takes two to four servings per day of various foods fortified with sterols and stanols (see list at right) to get the two grams a day needed to effectively reduce LDL levels. "A little bit here and a little bit there won't do any good," said Scott Grundy, director of the Center for Human Nutrition at the University of Texas Southwestern Medical Center in Dallas.

On the other hand, consumers "can't eat these foods limitlessly," said Grundy, who also has received industry support for his research. "When you do eat them, you have to cut down on appropriate amounts of other food. Otherwise, you could gain weight over the long term." That, in turn, can increase blood cholesterol levels.

Getting too much of the compounds themselves isn't a good thing, either. "We think that a safe level of intake is around three to five grams per day," Jones said. "It's theoretically possible . . . to exceed that."

Also, there is no evidence that people with healthy cholesterol levels can gain preventive benefits from eating foods fortified with stanols and sterols. For now, Grundy said, "people should have these products recommended by their physician to lower their blood cholesterol." So skip them, he said, unless your doctor advises you to eat them.

Plenty of healthy foods contain naturally occurring stanols and sterols. Among them: corn, sunflower, safflower, soybean and olive oils, almonds, beans, corn, wheat, lettuce, bananas, apples and tomatoes. Trouble is, it takes a large amount of these foods to match the fortified products. For example, you'd have to eat about13 cups of almonds--about 7,000 calories--to reach the recommended two grams.

Here's a rundown on some of the latest fortified products:

* Benecol caramel and chocolate chews. These sweet chews are available online at www.benecol.com. What they provide: 0.85 grams of stanols per piece. Calories: 20 per chew. Cost: $7.79 per bag of 20 chews; four bags for $28.95.

* CocoaVia chocolates. Produced by Mars, the candy company that makes M&M's and Dove chocolates, CocoaVia chocolate-covered almonds and other products were introduced in September. Find them at selected Wal-Mart and Target stores, and in early 2006 at Wegmans, Walgreen's and natural food stores. You can also buy CocoaVia online at www.cocoavia.com. What they provide: 1.1 to 1.3 grams of sterols per serving, depending on the product. Calories: 80 to 140. Cost: About $1 each; minimum order by mail $30.

* Lifetime low-fat cheese. Cheese is often off limits for those with elevated cholesterol, so here's a way to have cheese in four flavors: cheddar, extra sharp cheddar, mozzarella and jalapeno jack. Available at Safeway, Whole Foods and other chains as well as specialty stores and online at www.lifetimefatfree.com. What it provides: 0.65 grams of sterols per ounce. Calories: 55 per ounce, about half the calories of regular cheese. Cost: $3.99 to $4.99 per eight ounces.

* Minute Maid Heart Wise orange juice. This juiced-up juice can be found in most grocery stores. What it provides: one gram of sterols per eight ounces. Calories: 110 per eight ounces. Cost: $3.60 per half-gallon -- same price as other juice.

* Nature Valley Healthy Heart chewy granola bars. These bars come in honey nut and oatmeal raisin flavors. What they provide: 0.4 grams of sterols per bar. Calories: 160. Cost: about $2 to $3 per box of 12 bars -- comparable to other granola bars.

* Rice Dream Heartwise rice drink. This vegetable product can be used in place of milk on cereal, as a beverage or in recipes. What it provides: 0.65 grams of sterols per eight ounces. Calories: 130 to 140 per eight ounces, depending on the flavor. Cost: about $2.50 quart.

* Spreads. In 2000, Benecol and Take Control became the first margarine-like spreads with synthesized sterols and stanols to be approved by the Food and Drug Administration. SmartBalance OmegaPlus Buttery spread contains naturally occurring sterols that can be used in smaller quantities. All spreads are available at major grocery chains and many specialty stores. What they provide: 1.7 grams of stanols per tablespoon (Benecol); 0.45 grams sterols (SmartBalance), 1.7 grams sterols (Take Control). Calories: (Benecol) 70 per tablespoon; 50 (light); (SmartBalance) 80; (Take Control) 80. Cost/tub: About $5 (Benecol); $3.70 (Take Control), $2.49 (Smart Balance).

* Yoplait Healthy Heart yogurt. This yogurt with stanols comes in cherry orchard, harvest peach, strawberry and strawberry banana. What it provides: 0.4 grams per six ounces. Calories: 180. Cost: About $1.

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Eating them regularly can help fight "bad" cholesterol, say experts.