Nutritious asparagus low on calories

When spring weather is just right, an asparagus stalk can grow as much as 10 inches a day.

Even more impressive is what it can do for your diet. Asparagus is low in calories (about 5 calories a stalk) and is packed with vitamins A, C and E.

But where this edible member of the lily family truly shines is as a source of folate, a nutrient vital to good health. Folate is key for cell production and may help protect against heart disease, according to the American Dietetic Association.

Just a half-cup serving of asparagus delivers a third of the recommended daily intake of folate.

"Every nutrient is important but folate delivers a lot of bang for the buck," says Cynthia Sass, an American Dietetic Association spokeswoman. She adds that folate helps prevent birth defects and women of child-bearing age need to make sure they get enough.

(Other folate-rich foods include many fortified breakfast cereals, spinach, navy beans, orange juice and avocados.)

Eating plenty of asparagus is easy with recipes such as this one for braising it in olive oil with rosemary and bay leaves from Patricia Wells' new book, "Vegetable Harvest."

Wells says the simple braise brings out the mineral-rich, woodsy flavors of the asparagus, and the dish needs no further embellishment.

Green or purple asparagus would be the easiest options for this recipe, though green is the least expensive and most readily available. White asparagus, which is milder in flavor, also can be used. Most white asparagus should be peeled before cooking.

When shopping for asparagus, look for firm stalks with tight tips. Fresh asparagus should snap when bent. Though best eaten the day purchased, asparagus can be refrigerated, wrapped in a damp cloth inside a plastic bag, for three days.

Opinion is divided, but many people believe large stalks are sweeter and juicer than thin ones. White asparagus tends to be less flavorful. Purple asparagus will have a fruity flavor.

Peeling tough-skinned stalks with a vegetable peeler will help ensure that the tips and stalks cook at the same rate. And be sure to rinse all asparagus thoroughly before cooking to remove any lingering sand.

For an even simpler preparation, try microwaving a pound of asparagus with a few tablespoons of water in a covered glass dish for about 3 minutes, or until tender.

To roast asparagus, place the stalks on a baking sheet, drizzle with a tablespoon of extra-virgin olive oil, and roast at 500 F for 10 minutes, or until wilted and browned in spots.

ASPARAGUS BRAISED WITH FRESH ROSEMARY AND BAY LEAVES

(Start to finish: 15 minutes)