Onions are low in calories yet add abundant flavor to a wide variety of foods.

With only 30 calories per serving, onions are sodium, fat and cholesterol free, and provide dietary fiber, vitamins C and B6, potassium and other key nutrients.

Higher intakes of fruits and vegetables have been associated with a variety of health benefits.

Research shows that onions may help guard against many chronic diseases. That's probably because onions contain generous amounts of a flavonoid called quercetin.

Other sources are tea and apples, but research shows that absorption of quercetin from onions is twice that from tea and more than three times that from apples.

Studies have shown that quercetin protects against cataracts, cardiovascular disease and cancer.

In addition, onions contain a variety of other naturally occurring chemicals known as organosulfur compounds that have been linked to lowering blood pressure and cholesterol levels.

Healthy and flavorful onions serve as the core of this classic soup and a soon-to-be family favorite - bruschetta.

4 large yellow onions (about 9 to 11 ounces each), sliced6 tablespoons butter or margarine1 tablespoon sugar2 quarts reduced sodium chicken broth½ cup brandy (optional)Salt and pepper, to taste½ baguette French bread, sliced, toastedGrated Romano cheeseMelt butter in a large saucepan that holds at least 4 quarts. Add onions; cook over medium heat 12 minutes or until tender and golden. Stir often.Add sugar and cook, stirring for 1 minute. Add broth; cover and bring to a boil. Reduce heat; simmer 12 minutes.If desired, add brandy; cook 2 minutes longer. Season with salt and pepper. To serve, ladle soup into bowl; float toast on soup. Sprinkle with cheese.Makes 6 servings.

1 French bread baguette (about 8 ounces)4 ounces light cream cheese½ cup nonfat or low fat ricotta cheese2 teaspoon dried oregano2 teaspoons dried basil1 cup pizza sauce, canned1 medium onion, cut into paper-thin wedges¼ cup Parmesan cheese, gratedParsley flakes (optional)Split bread in half lengthwise. Pull out some bread from center of each half, leaving a ½-inch shell.Beat cheeses and herbs with fork and spread mixture along length of both bread halves.Place a ribbon of pizza sauce and a single layer of onions over cheese mixture. Sprinkle with Parmesan cheese and bake on baking sheet at 400 degrees for 30 minutes or until onion is tender and tips are slightly blackened, but crust is not too dark.Sprinkle with dry parsley flakes if desired. Cut crosswise into narrow strips.Makes 8 servings.