"Hypertension" means high blood pressure, not nervous frustration. But if the doctor has just told you that because you have high blood pressure you must give up salt, pizza, Chinese food, pickles and other savory delights, you may be climbing the walls.

Several local dieticians report that a low-salt - or more specifically a low-sodium - diet is one of the hardest to stick to. For those diners who think reaching for the salt is part of sitting down to the table, food can taste very bland without NaC1(sodium chloride).

In addition, most processed foods, from soup to beer nuts, are loaded with salt. So are meals prepared at restaurants, or even by your friends. Salt deprivation is all the more bewildering when the doctor advises a low-sodium diet, but doesn't explain how to do it.

According to the National Center for Health Statistics about 35 million Americans are affected by hypertension. Their blood pressure is high enough to put them in serious risk of heart disease or stroke. Cutting sodium out of the diet consistently has been found effective in bringing down blood pressure in hypertensive patients - and the major source of sodium in food is salt. There are 2.3 grams of sodium in just one teaspoon of salt and that may be as much as the recommended daily intake for a hypertensive individual.

For some patients, the physician may recommend eliminating only the salt that is added in cooking or at the table. This means relying more heavily than usual on herbs (such as rosemary, basil, murjoram, thyme, dill and tarragont, spices (such as curry, mace, ginger, cinnamon and cloves and flavorings like lemon juice, vinegar and wine. Stay away from cooking wine, however, there's usually a lot of salt added.

Of course, no amount curry powder or oregano will ever give food that familiar salty taste, and a heavy hand can make your meal very spicy or bitter. By experimenting, one can achieve pleasing alternatives, and it simply takes takes trial and error to develop your own favorites.

While fresh herbs do not need to be cooked to taste good, some of the dried ones do. Of the dried variety, dill, mint, chives and parsley flakes work particularly well on salads, uncooked dressings and other cold dishes. For variety, don't overlook seeds, such as poppy, caraway and sesame.

In many cases of hypertension, the doctor may recommend that processed foods containing sodium be avoided, too. If so, it's necessary to get in the habit of reading labels. It is obvious that pretzels and sardines are high in salt, but there's also salt hidden away in catsup, mustard, soup, peanut butter, cake mix, cheese, and most other processed foods.

When reading labels, look for preservatives, colorings and other compounds that contain sodium. A few common ones are sodium phosphate, sodium benzoate, sodium hydroxide. Baking powder and baking soda have sodium, too, as does MSG - monosodium glutamate.

There are products made specifically for people on low-sodium diets. Low-sodium V-8 juice. Campbell's soups, peanut butter, cottage cheese and bread along with unsalted margarine are stock in either the diet or dairy sections at local supermarkets. A&P and Giant also carry unsalted tuna in water. If you can't find these products on the shelf, the stores say they will order them for you.

Some health food stores offer no special low-sodium products; others, a broad selection. Salt-free catsup and chili sauce, which many hamburger lovers think they cannot live without, can be found at Custom Grown Diet Foods in Bethesda; Ecology Mart in Silver Spring; Vita Health Food, 1010 F St. NW; Kennedy's Natural Foods, at four suburban locations; and Woodlawn Natural Food Center in Arlington.

These stores also offer low-sodium cheeses, crackers, salad dressing, mayonnaise, seafood, and some carry cake or pancake mixes. As for snacks, YES! in Georgetown and Sun and Earth Natural Foods in Bethesda offer salt-free potato chips and corn chips; Golden Harvest in Gaithersburg stocks salt-free pretzels (these stores also offer some of the products listed above).

Most health food stores stock raw, unslated nuts and an unsalted vegeatble seasoning powder which can be used during cooking or at the table. The seasoning most commonly found in this area is called Vegit.

In many cases, salt-free products cost more than their salty counterparts, because of the lower sales volume. On a recent trip to Safeway, Campbell's 10 3/4 ounce cream of mushroom soup was selling at three cans for $1; it cost almost as much, 89 cents, for three 7 1/4-ounce cans that were low-sodium. V-8 juice was 99 cents for six 6-ounce cans; for low-sodium V-8, the price was $1.09.

As though it's not enough that you may have to visit stores and markets all around town and pay higher prices, some low-sodium foods taste like cardboard, no matter what brand you try. But, with vegetables there is no need to suffer. Most vegetables frozen without sauce are not salted. Frozen peas and lima beans are the exception, because they are floated in brine (salt water) before packaging to separat one grade from another.

Another way to solve the taste problem is to shun low-sodium convenience foods and prepare your own soups, spaghetti sauce, mayonnaise, salad dressing, cookies and bread. Follow your favorite recipes but leave out the salt, and experiment with additional spices or other seasonings.

Even uncooked, unprocessed foods have a certain amount of sodium. It is difficult, short of fasting, to avoid consuming 450 to 500 milligrams a day. On the most restricted diets, it is necessary to avoid or limit foods naturally high in sodium, such as milk, spinach, celery and certain meats. If you are counting milligrams, the U.S. Department of Agriculture publishes "Nutritive Value of American Foods," which lists sodium gram content and other nutritional information.

The doctor may spell out very clearly just what foods are allowed a hypertensive patient, and in what quantities. If not, or if additional suggestions are needed on meal planning, the American Heart Association offers publications outlining low-salt menus and recipes; so do the Fairfax and Arlington Counties Cooperative Extension Services. All these publications are free.

Over the past six years, my has been experimenting with low-salt recipes, and has developed a collection that are tasty whether or not you are on a restricted diet. Since hypertentive individuals usually are cautioned to limit calorie intake as well as salt (and because this is the way she cooks), these recipes do not call for added sugar or fat. A few of them follow. SUE'S TOMATO SAUCE (Makes 2 to 2 1/2 cups) 2 small onions, chopped 1 green pepper, diced 2 cloves garlic, crushed 1 tablespoon oil (optional) 4 large, very ripe tomatoes, or 1 can (16 ounces) low-sodium tomatoes 3/4 cup unsweetened apple juice or sherry 1 bay leaf 1/4 teaspoon basil 1/4 teaspoon marjoram$"1/8 teaspoon cloves Pepper to taste

Heat the oil in a saucepan and saute the onions and green pepper with the garlic. Cook until the onions are transparent. If you wish to avoid using the fat, steam the vegetables in 1/4 cup water. In this case, keep the pan covered and stir frequently, replenishing the water if the vegetables begin to stick.

Skin, seed, and cut up the tomatoes. Add them to the onions, along with the apple juice (or sherry) and seasonings. Lower heat, cover, and simmer for 30 minutes. Stir occasionally. If sauce is too thick, add water or low-sodium tomato juice to achieve the desired consistency. BAKED FISH (4 servings) 4 fillets of trout, bluefish or other fresh fish 2 tablespoons lemon juice 2 cups tomato sauce

Preheat oven to 350 degrees. Put fish fillets in a baking dish, skin side down. Cover with lemon juice. Add tomato sauce and bake for 10 to 15 minutes. ZUCCHINI CASSEROLE (6 to 8 servings) 1 tablespoon oil (optional) 1/2 pound mushrooms, sliced 2 pounds zucchini 1/4 teaspoon rosemary, crushed 2 cups tomato sauce

Saute mushrooms in hot oil until transparent. If you wish to avoid using oil, steam the mushrooms in a small amount of water. Keep the pan covered, stir frequently and add water to prevent mushrooms from sticking.

Cut zucchini crosswise into round slices and sprinkle with rosemary. Place in a baking dish, alternating layers of tomato sauce, zucchini and mushrooms, ending with tomato sauce. Bake in preheated 350-degree oven for 35 to 45 minutes. CHICKEN WITH PEACH SAUCE (4 servings) 1 chicken, cut up Juice of 1 lemon 1/4 teaspoon mace 1/4 teaspoon ginger Paprika 1 can (1 pound) unsweetened peaches (syrup only)

Preheat oven to 325 degrees. Mix ginger and mace in the lemon juice, and pour over chicken pieces. Place the chicken, skin side down, in a baking dish and bake uncovered for 30 minutes. Turn the pieces and bake for another 30 minutes.

Sprinkle the chicken lightly with paprika and add the syrup from the cap of unsweetened peaches, about 1 cup. (Unsweetened fruit usually is found in the diet section of the supermarket) Transfer chicken to the broiler and cook for 15 minutes or until the skin is dark and crisp, basting frequently. GLAZED CARROTS (4 to 6 servings) 1 pound carrots 1 cup water 1 teaspoon low-sodium vegetable seasoning 3 tablespoons honey 1/4 cup finely chopped parsley

Peel carrots and cut them in thirds. Place in a skillet and add water vegetable seasoning. Bring water to boil, then cover, turn down the fish and simmer for 20 minutes. If all the water evaporates replenish it so that just a few tablespoons remain when the carrots are almost tender.

Add honey and cook for 5 minutes, stirring occasionally to coat the carrots. Toss with parsley and serve. POPPY SEED BREAD (Makes 2 loaves) 2 packages yeast 1/2 cup warm water 2 large potatoes, enough to yield 2 cups when mashed 1 1/2 cups potato water 7 to 8 cups unbleached flour 1 to 2 tablespoon poppy seeds 1 egg white mixed with 1 tablespoon cold water (optional)

Dissolve yeast in 1/2 cup warm water and set aside.

Wash potatoes and cut them in large chunks. Boil them in the skins until tender, then drain them and reserve the water. Peel the potatoes and put them through a sieve. (This takes a little extra time, but as a result you won't have any hard lumps in the bread.)

When the potato water has cooled add 1 1/2 cups to the mashed potaotes and mix well. Stir in the proofed yeast and 1 tablespoon poppy seeds. Gradually stir in as much of the flour as you can - at least 6 cups.

Turn the dough out on a floured board and knead for 15 minutes, adding remaining flour until you have a soft, resilient dough that is not sticky. Shape the dough into a ball.

Place in an oiled bowl and turn the dough until the whole surface is coated with oil. Cover and let rise in a warm place until double in bulk - about 45 minutes (bread rises much faster without the salt). Punch down the dough, knead for just a few minutes and divide in half.

Turn half the dough onto a floured board and roll it out into a rectangle about 1/4 inch thick. Start at one of the narrow ends and roll up the dough tightly into a loaf. Pinch the edges together and tuck underneath the loaf, then place in a greased 9-by-5-inch bread pan. Repeat for the second loaf. Cover and let rise for another half hour.

Preheat oven to 400 degrees. Slash the top of the loaves in one or two places and bake for 45 minutes. If desired, brush the top of the loaves with the egg white mixture and sprinkle with poppy seeds about 15 minutes before the bread is done. CUCUMBER RAITA (4 to 6 servings) 2 medium cucumbers, pared and thinly sliced 2 teaspoons salt 10 ounces unflavored yogurt 1/2 teaspoon sugar 1/4 teaspoon powdered cumin 1/2 medium onion, finely chopped

Sprinkle 1 teaspoon of the salt over the cucumbers and let them stand for at least 1 hour. Drain thoroughly, in another bowl whisk together th yogurt, remaining 1 teaspoon salt, sugar and cumin until the yogurt is smooth. Stir in the cucumbers and the onion. Chill. If you wish, you may garnish the raita with 2 tablespoons finely chopped fresh coriander leaves.

From "Not Everything We Eat Is Curry," by Aravinda Chakravarti and Donald C. Morizot.

Note: You may wish to use an 8-ounce carton of yogurt and cut any salt. CHILLED BEET SOUP (1 1/4 quarts) 1 container (8-ounces) sour cream 1 can (16 ounces) diced beets 3 teaspoons beef bouillon granules dissolved in 2 cups boiling water 2 tablespoons dark brown sugar 2 tablespoons lemon juice 1/2 teaspoon salt 1/8 teaspoon white pepper 2 small scallions, thinly sliced Several sprigs fresh dill, minced

Empty the cream into a medium bowl. Holding back the beets with the top of the can, gradually whisk the beet juice into the sour cream, keeping smooth. Stir in the beets and the remaining ingredients. Chill thoroughly. Stir well before serving. RED PEPPER AND CHEESE SANDWICHES (About 2 cups) 8 ounces natural cheddar cheese, grated medium-fine 1/2 cup drained and finely chopped pickled sweet red pepper slices, from a 1-pint jar 1/2 cup chopped (medium-fine) walnuts 1/2 cup mayonnaise 2 tablespoons prepared mustard 1 tablespoon bottled white horseradish Sliced bread

Mix together the cheese, pepper, walnuts, mayonnaise, mustard and horseradish; chill. Use us the filling for the bread for sandwiches. BANANA OAT BREAD 1 1/4 cups all-purpse flour 4 teaspoons baking powder 1 teaspoon salt 1/2 teaspoon cinnamon 1 cup pureed ripe bananas (about 3 medium) 2 eggs 1/2 cup corn oil 1/2 cup sugar 1 cup quick-cooking oats 1/2 cup chopped (medium fine) walnuts

On wax paper stir together the flour, baking powder, salt and cinnamon. In a medium bowl beat together until blended the bananas, eggs, oil and sugar, add the flour mixture; stir just until dry ingredients are moistened. Stir in the oats and nuts.

Turn into an oiled 8-by-4 1/2-by-2 1/2-inch loaf pan. Bake in a preheated 350-degree oven until a cake tester inserted in the center comes out clean - about 55 minutes. Cool on a wire rack for 10 minutes. Loosen edges and turn out on rack. Cool completely. BLUEBERRY CAKE 2 cups all-purpose flour 2 teaspoons baking powder 1/2 teaspoon salt 1/4 cup butter or margarine 3/4 cup suagr 1 large egg 1/2 cup milk 2 cups fresh blueberries Streusel (see below)

Stir together the flour, baking powder and salt. Cream the butter and sugar, beat in the egg. Add the flour mixture and the milk; stir only until the flour mixture is moistened. Fold in the blueberries. Turn into a greased and floured 9-inch springform pan. Sprinkle with the streusel

Bake in a preheated 375-degree oven until a cake tester inserted in center comes out without any batter clinging to it - 45 to 50 minutes. If streusel gets very brown before cake has baked place a sheet of foil over the top. Cool on a wire rack for about 5 minutes; loosen edges and remove springform band. Serve warm.

Streusel: Stir together 1/2 cup firmly packed light brown sugar, 3 tablespoons flour and 3 teaspoons cinnamon; cut in 3 tablespoons butter until fine, stir in 1/2 cup finely chopped nuts.