It's not a diet, it's a way of life -- a prescription for good health that hasn't changed in thousands of years.

It's the Mediterranean diet, a catchall phrase that includes the foods generally eaten on the edges of the Mediterranean Sea, from Spain to Italy to Greece to Lebanon to Morocco and Tunisia.

Study after study has found high correlation between the typical diet of the people of this region and general good heath. Interest in the studies, and in the diet, has spawned a slew of cookbooks and created new markets for such Mediterranean foodstuffs as couscous, lentils, and olive oil.

Increasingly, food with a Mediterranean focus is showing up on restaurant menus, as chefs and consumers seek food that is full-flavored and health-enhancing at the same time.

"It's simple food, simply prepared," says Linwood Dame, owner of Linwood's-Due and chef at Linwood's in Owings Mills. He has long prepared food Mediterranean-style in his restaurants.

"The emphasis is on freshness, seasonal availability," says Due chef Mark Hoffman. "There's also an emphasis on pastas, grains and beans."

"Those things are accented with things like olives, garlic, wild berries and figs," Mr. Dame adds. "But all of the foods are things that stand up well on their own."

One of the most important aspects of the Mediterranean way of thinking about food, Mr. Hoffman says, is shopping. It's important to find the best-quality ingredients. A simple dish, such as Due's linguine with arugula and black olives, finished with a little olive oil, depends heavily on the quality of its individual parts to provide sensational taste.

There is a working definition of the Mediterranean diet, devised during a conference held early last year in Cambridge, Mass. As reported by Nancy Harmon Jenkins in her new book "The Mediterranean Diet Cookbook" (Bantam Books, $27.95), participants in the conference, sponsored by Harvard School of Public Health and by Oldways Preservation & Exchange Trust, described the diet as:

"Plentiful fruits, vegetables, legumes and grains; olive oil as the principle fat; lean red meat consumed only a few times per month, or somewhat more often in very small portions; low to moderate consumption of other foods from animal sources, such as dairy products (especially cheese and yogurt), fish, and poultry; and moderate consumption of wine [primarily at meals]."

"The main thing that sets [Mediterranean cuisine] apart is the fresh ingredients," says J. Ashley Sharpe, chef of Piccolo's of Fells Point.

"It's always been a healthy cuisine," Mr. Sharpe says. "There are not a lot of creams . . . and of course, the use of olive oil. It's cuisine that's quick and simple so you can get on with the pleasures of life."

At Piccolo's, which features the cuisine of Tuscany, the philosophy results in such dishes as pasta with chicken, artichoke hearts, sun-dried tomatoes and olives, and broiled oysters with pancetta, fennel, a touch of Pernod and a touch of Parmesan cheese. Mr. Sharpe also offers a saffron risotto with seafood.

'They let food speak for itself'

"It's my style of eating," says Holly Forbes, executive chef at the Harbor Court Hotel. "Because it's fresh. They let the food speak for itself. There's not a lot of contrivance." For the hotel's monthly Cellarmasters dinner earlier this week, Ms. Forbes and new Hampton's restaurant chef Scott Hoyland created a Mediterranean menu of bouillabaisse (fish stew), roasted eggplant and tomato terrine and Majorcan-style duck with green olives, herbed potatoes and braised fennel.

The variety of cuisines represented in the Mediterranean region gives a cook's imagination wide scope, Ms. Forbes says. "On the east coast you have Lebanon, and on the west coast you have Spain. Humble foods run through my mind when I think of Provence, and exotic things when I think of Morocco."

She too finds the freshness and simplicity of the food appealing. "I think so much of the cuisine is defined by the purity of the ingredients, from the sea, and what they grow." The result, she says, is "simple presentations and bold flavors."

While the benefits of eating this way -- lower incidences of heart disease, cancer, and diabetes, and good health and vigor continuing into old age -- are clear, there is some controversy over a blanket recommendation that people adopt the diet, because of the amount and the kind of fat involved.

The U.S. Department of Agriculture currently recommends that Americans' diets contain no more than 30 percent of calories from fat.

Fat is the issue

"Central to any comparison of Mediterranean and American diets is, of course, the issue of fat," Ms. Jenkins writes. "Most of the fat consumed in the United States is highly saturated fat from meat and dairy products, principally red meat and milk. In Greece, when the Mediterranean diet studies began in the 1960s, a full 40 percent of calories in the diet came from fat, while in Southern Italy the figure was 29 percent. In both cases, however, most of the fat consumed came from olive oil."

Olive oil, she notes, is high in monounsaturated fats, which lower the "bad cholesterol" LDLs (low-density lipoproteins), and high in such antioxidants as vitamin E; it appears that olive oil can be beneficial in the diet if it is the only fat used.

That "only" is what keeps the Mediterranean lifestyle from being a natural for most Americans.

Mr. Dame says: "We can't do it exactly like they do in the Mediterranean, because we don't have the same climate. . . . Instead, we can put our own flair to it. The idea is to stay within the framework."

It's inevitable that more elements of the Mediterranean will make their way into the American mainstream, Mr. Dame says. "Ten years ago olive oil was not a big deal."

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This recipe is from J. Ashley Sharpe of Piccolo's.

Mediterranean Stuffed Pork Loin

Serves 4 to 6

FOR THE PORK LOIN:

1 1/2 pounds cleaned and trimmed center cut pork loin

2 tablespoon Dijon mustard

1 tablespoon minced garlic

1/4 cup finely chopped fresh basil

2 teaspoons salt

1 tablespoon black pepper

1 cup red wine

1/2 cup of strong beef broth

FOR THE STUFFING:

1/2 cup sun-dried tomatoes

1/2 cup chopped fresh basil

1/2 cup toasted pine nuts

1/4 cup bread crumbs

1 tablespoon garlic

1 egg

2 tablespoons heavy cream

salt and pepper to taste

Rehydrate sun-dried tomatoes in warm water until malleable and drain off liquid. Combine all stuffing ingredients in a food processor and blend until it becomes a smooth paste, stopping often to scrape down sides and blade.

Remove excess fat and outer membrane from pork loin. Form a pocket in loin by cutting straight through center of loin with a boning knife, being careful not to go through sides of the loin. This should form a pipe-like pocket, something like an elongated doughnut. Push stuffing into pocket with your hand so it is solid throughout the loin. Mix the garlic, Dijon, basil, salt and pepper together and rub it over the stuffed loin. Let it sit in the refrigerator for a few hours.

Heat the oven to 325 degrees.

Heat a tablespoon of olive oil until hot, and sear the loin on all sides, not allowing it to burn. Place loin in a sealed baking dish with wine and beef broth. (If you don't have a lidded dish, use a deep pan and cover it tightly first with plastic wrap and then foil, making sure the plastic wrap isn't touching the loin.

Bake loin for 30 to 40 minutes, until internal temperature 'N registers 140 degrees on a meat thermometer. To make sauce, remove the loin to a platter and keep warm. Reduce braising liquid until 3/4 cup to a cup of sauce is left.

Per one of 6 servings: calories, 546; protein, 36 g; fat, 30 g; sodium, 2,847 mg; carbohydrates, 17 g

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This recipe is from Mark Hoffman at Due.

Salmon Loin in Swiss Chard With Plum Sauce

Serves 6

FOR THE SALMON:

6 6-ounce salmon fillets, skinless, boneless

12 red Swiss chard leaves, stems removed

1 10-ounce box couscous

2 cups dried fruits, rehydrated then diced small (see note)

kosher salt, to taste

FOR THE PLUM SAUCE:

10 plums, pitted and chopped up

1 1/2 cups sugar

1/2 cup water

1/4 cup port wine

In boiling salted water, blanch the Swiss chard for approximately 45 seconds. Remove and immediately drop into ice water. Let cool and drain. Pat dry with paper towels.

Season salmon with kosher salt. Carefully fold two Swiss chard leaves around each salmon fillet, folding the leaves underneath. Steam salmon for about 6 minutes, or until desired doneness.

Meanwhile, prepare the couscous according to directions on the box. At the end, mix in the rehydrated chopped fruits.

To make plum reduction, caramelize the sugar and water by placing them in a nonreactive saucepan over low heat. When the sugar water begins to turn light brown, watch it closely. When it begins to turn golden brown, add the plums slowly. Be cautious, as the mixture will foam up. Let plums simmer for 15 to 20 minutes. Remove and puree sauce. Strain sauce through fine strainer. Keep warm. Finish with a little port wine.

To serve, spoon couscous onto 6 individual plates, or onto serving platter. Use a spatula to place the salmon fillets on the couscous. Drizzle salmon with a little rosemary-infused olive oil (recipe follows). Spoon plum sauce around couscous.

Note: To rehydrate the fruit, place in hot water for several minutes, remove and drain.

Per serving: calories, 818; protein, 41 g; fat, 11 g; sodium, 1246 mg; carbohydrates, 138 g.

Rosemary-Infused Olive Oil

1 cup olive oil

1 sprig rosemary

Simmer olive oil and rosemary over low heat for 5 minutes. Remove from heat and let sit one hour. Can be stored (unrefrigerated) for six months.

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This recipe is from "The Mediterranean Diet Cookbook" by Nancy Harmon Jenkins.

Tomato and Other Vegetable Pilafs

Serves 6

1 1/2 cups clear white chicken stock or vegetable broth

1 pound tomatoes, peeled, or 2 cups canned whole tomatoes, drained

1 medium onion, chopped

1/2 garlic clove, crushed with the flat blade of a knife

2 tablespoons extra-virgin olive oil

1/4 teaspoon ground cinnamon

1/2 teaspoon sugar

1 1/2 cups long-grain rice

salt and freshly ground black pepper to taste

about 1/4 cup chopped fresh green herbs such as parsley, basil or cilantro (optional)

Heat stock to a slow simmer while you prepare the rest of the pilaf.

Chop peeled tomatoes coarsely and drain off excess juice in a sieve. If you're using canned tomatoes, crush them coarsely with a fork.

Gently saute onion and garlic in the oil in a saucepan over medium-low heat until the vegetables are soft but not browning, about 15 minutes. Add tomatoes, cinnamon, and sugar and cook over gentle heat for about 5 minutes or until they are soft.

Add the rice and stir to mix well. Cook for another 5 minutes, then pour in the simmering stock. Stir once to mix, then cover and cook for about 15 minutes, or until the rice is tender and the liquid has been absorbed. Remove from the heat and set aside, covered, for 5 minutes.

Stir in the herbs and serve immediately.

Per serving: calories, 250; protein, 4 g; fat, 7 g; sodium, 338 mg; carbohydrates, 43 g.

READ ALL ABOUT IT

Interest in Mediterranean cuisine has resulted in a profusion of cookbooks focused on the region. Here are some of the more recent:

* "The Mediterranean Diet Cookbook: A Delicious Alternative for Lifelong Health," by Nancy Harmon Jenkins, the founding director of Oldways Preservation & Exchange Trust (Bantam Books, $27.95). A good introduction to Mediterranean cuisine in an almost scholarly presentation. No pictures, but plenty of tips and a glossary.

* "Mediterranean the Beautiful Cookbook," by Joyce Goldstein, San Francisco chef and owner of the restaurant Square One (HarperCollins, $45). A feast for the eye as well as the palate, Ms. Goldstein's book contains 250 recipes from Spain, France, Italy, Turkey, the Middle East and North Africa. It is packed with stunning pictures of the food and of the regions covered.

* "The Cooking of the Eastern Mediterranean," by respected cookbook author Paula Wolfert (HarperCollins, $30). Ms. Wolfert spent five years traveling and collecting recipes for the book, which focuses on four regions: Slavic Macedonia, Turkey, the Levant, and the Republic of Georgia. Recipes range from Turkish dumplings with yogurt sauce to red lentil soup from Aleppo (Syria), roast chicken stuffed with lamb, rice and pine nuts to cherry bread pudding. There are notes and tips throughout.

* "James McNair Cooks Italian," by popular San Francisco author James McNair (Chronicle Books, $24.95). More than 150 recipes, beautifully illustrated, ranging from risotto with Parmesan cheese to grilled lamb chops, to fresh fig tart.