"Don't mess with my Thanksgiving dinner this year, please," said an anxious reader. "Whatever crazy Thanksgiving menu you print each year, my wife decides to try it. One year you did low calorie. I was starved by 9 o'clock. Another time you did vegetarian. I want my turkey!"

"Anxious reader" sympathized with the plight of those who must dream up something new to say about holiday food, but only to a point.He doesn't want his tradtions fooled with too much. Maybe a modification here and there. Possibly a new dish . . . as long as the old ones remain in place.

So this year's menu should please all traditionalists. We begin with roast turkey, giblet gravy and bread stuffing. This is accompanied by yams, and/or mashed potatoes, broccoli with lemon butter, cranberry-orange relish, whole wheat raisin bread, vegetable relish tray and for dessert, pumpkin pie. There is wine with the turkey, or hot cider if you prefer. With dessert, coffee or tea.

The emphasis is on fresh, minimally processed foods: a plain turkey without factory basting; stuffing made from bread, not stuffing mix; gravy from scratch; fresh not canned yams; homemade bread; pumpkin pie filling made at home.

The emphasis is also on advance preparation so that the cook or cooks can spend time with their guests instead of in the kitchen. The bread and pie can be made ahead and forzen. The broth for the dressing and gravy can be made a day ahead and refrigerated. So can the dressing itself, though it shouldn't be put in the turkey until just before roasting. The relish can be made several days in advance and refrigerated.

And, of course, the table can be set the night before. That leaves preparation of the broccoli, yams, mashed potatoes and the gravy for Thanksgiving day. Naturally the turkey has to be roasted, but you don't have to hold its wing while it cooks.

In addition to the emphasis on advance preparation and fresh foods, some changes have been made in the accompanying recipes. Changes which have turned an old-style traditional Thanksgiving dinner into a festive dinner, for the health- and diet-conscious 1980s.

This dinner has less fat, less salt, less cholesterol and less sugar than its traditional counterpart. It also has more of the complex carbohydrates-fruits, vegetables and whole grains. As a matter of fact, its recipes have been modified in such a way that the meal is patterned after Dietary Goals for the United States.

But it will take the trained eye of a nutrition expert to spot the differences. Working on the premise that most Americans may be willing to go along with some changes in their eating habits in order to live longer, healthier lives, but will balk if the changes are too drastic, Linda Smith, a nutritionist with Community Nutrition Institute, has come up with a Thanksgiving menu which is hard to distinguish from the traditional.

Based on the assumption that on Thanksgiving Day most people eat only two meals, the menu uses about 2/3 of the daily intake, leaving 1/3 for breakfast or brunch. For men there is even an allowance for a late night snack. (It is based on 1,800 calories, a little low for most men, a little high for most women.)

While Dietary Goals are not perfect, they form the basis for the recommendations made in the Surgeon General's report, Healthy People, and the dietary guidelines suggested by the U.S. Department of Agriculture and the Department of Health, Education and Welfare last month.

USDA is struggling now to translate the guidlines into menus and recipes people will find applealing. Smith's menu is a long way from those recommended by a USDA nutritionist who, several years ago, set out to prove that no one would follow Dietary Goals because you'd have to eat 13 slices of bread a day to do so.

Smith assumes that people will consume two-thirds of their daily intake at the Thanksgiving dinner yet the meal only offers two slices of bread. If you can only eat 3 ounces of turkey, and you can't eat any skin. You can only use 2 teaspoons of butter for your bread. You will have to limit yourself to 8 ounces of wine and a single serving of most of the dishes, or choose vegetables instead of stuffing and gravy for seconds. You will have to refrain from using the salt shaker even if you don't find the food salty enough for your palate.

While Smith has created a menu with white potatoes and yams, because she says, "I can't have Thanksgiving dinner without mashed potatoes," many people would be willing to give up one or the other. Smith had suggested a choice of yams or cranberry-orange relish. It could just as easily be relish in place of the mashed potatoes.

If the cook isn't a baker, it is possible to substitute one of the many delicious whole grain breads available at bakeries.

There's a limit to how much experimenting you may be willing to do on Thanksgiving, America's greatest food holiday, but we'd love to hear from anyone who does, cooks and eaters all. THE MEAL 3 ounces of light and dark meat turkey, mostly light meat, no skin 1/2 cup bread stuffing 1/4 cup gravy 1 serving of yams 1/4 cup cranberry orange relish or 1/2 2/3 cup mashed potatoess 2 1/2 spears broccoli with 1 teaspoon of butter 2 slices whole wheat bread, each 1/2-inch thick with 2 teaspoons sweet butter Vegetable relish tray-unlimited carrots, celery, radishes 1 slice (or 1/8 of recipe) of pumpkin pie 2 glasses, 4 ounces each, white wine THE TURKEY One 12-pound fresh or frozen plain turkey A few tablespoons oil Large brown paper bag

Thaw turkey according to package directions. Preheat oven to 325 degrees. Brush bird with oil, especially the outside wings. Put bird into a double-thick grocery bag (make sure there are no holes in the bag).Tie a string around the bag opening so bag is tightly closed. Place in large broiler pan. Bake 4 to 5 hours. (Allow 20 minutes per pound for turkey over 12 pounds). Do not open bag until turkey is completely cooked and ready to take from oven.

Three ounces of turkey contain approximately 162 calories, 26 grams of protein, 5 grams of fat, 111 mg of sodium, 1.5 grams saturated fat and 112 mg cholesterol. TURKEY GRAVY Fat-free broth with onions and celery (see recipe below) 1/4 to 1/3 cup cooked turkey neck meat 2 tablespoons whole-wheat flour 1/2 teaspoon salt

Put 1/4 cup broth and flour in a 1-quart saucepan. Stir over low heat until a smooth paste is formed, then add up to 1 1/4 cups of remaining broth (left over from following recipe), meat and salt. Cook over low heat, stirring constantly until thickened.

One-quarter cup of gravy contains approximately 25 calories, 1 gram of protein, 5 mg carbohydates, 50 mg sodium, negligible fat and cholesterol.

When making the following stuffing, prepare turkey stock a day ahead: BREAD STUFFING (Makes 7 cups) Stuffing: 4 cups toasted or stale whole wheat or 7-grain bread crumbs (10 slices or 6 cups uncooked) 1 cup onion or scallions, finely chopped 1 cup celery, finely chopped 1 cup walnuts, chopped 2 egg whites 1 1/4 teaspoons rosemary (optional) 1 teaspoon fresh dill, chopped (optional) 1 teaspoon each thyme and sage 1/2 teaspoon salt 1 1/4 cups turkey stock Turkey stock: Turkey innards (neck, heart, liver) 1 bay leaf 1 stalk finely chopped celery 1 medium onion, chopped 1 teaspoons rosemary 1 teaspoon thyme 1 quart water

Make turkey stock by combining ingredients listed in a saucepan. Simmer, covered for about 2 hours until neck meat is cooked and falls easily off the bone. Chill until fat solidifies, then skim off fat.

Stuffing: Combine stuffing ingredients. Moisten with broth. Use to stuff a 12-pound turkey or place in a 2-quart casserole and bake, covered for 1/2 hour in a 325-degree oven, then uncover for another 1/2 hour and if necessary add more stock.

One-half cup of stuffing contains approximately: 61 calories, 3 grams protein, 10 grams fat, 14 grams carbohydrates, 184 mg sodium, no cholesterol and negligible saturated fat. MASHED POTATOES 9 medium potates, unpeeled 3 tablespoons butter 3 tablespoons vegetable oil 3/4 cup skimmed milk 1/2 teaspoon salt Freshly grated pepper to taste

Wash potatoes, place in a sauce pan with enough water to cover and boil until tender. Drain and dry carefully. Mass unpeeled, cooked potatoes with butter, oil, milk and salt until all lumps are gone. Serve with freshly grated pepper.

One-half to 2/3 cup serving contains: 127 calories, 2.1 grams proten, 1.7 grams fat, 25 grams carbohydrates, 127 mg sodium, 1 gram saturated fat and 66 mg cholesterol.

This bread can be made the weekend before Thanksgiving and frozen. WHOLE WHEAT RAISIN BREAD (Makes 3 loaves) 1 package dry yeast 3 1/2 teaspoons honey 3/4 to 1 1/2 teaspoons salt 3 cups whole-wheat flour 3 cups unbleached flour 1 cup raisins Cornmeal

Dissolve yeast in 1/2 cup warm water. Add 1/2 teaspoon honey and set aside until foamy. In a large mixing bowl combine 1 1/2 cups warm water, 3 teaspoons honey, salt and yeast. Combine flours. Gradually beat in 2 cups of the combined flours. Cover and let stand a few minutes. Add remaining flour, a cup at a time. Turn out onto a floured board and knead well, until dough is smooth and satiny. Shape dough into a ball, place in a warm greased bowl, cover with wax paper. Let rise until doubled, about 1 hour.

Knead dough again, working out all air bubbles. Add raisins. Shape into 3 loaves. Place loaves on a greased baking sheet sprinkled with cornmeal. Cover and let rise in a warm place until doubled.

Preheat oven to 350 degrees. Slash the tops of the loaves and place in oven. Bake for 40 to 45 minutes.

A 1-inch slice of this bread contains: 106 calories, 22 grams carbohydrates, 4 grams sugar, 50 mg sodium and no fat. FRUITED AND SPICED YAMS (6 to 8 servings) 3 1/2 cups thinly sliced washed, unpeeled yams (about 1 1/2 pounds) 2 red apples unpeeled, washed and thinly sliced 1 teaspoon cinnamon 1/4 teaspoon cardomom 1/2 teaspoon nutmeg 1 cup orange juice

Wash yams carefully; do not peel. Slice thinly. Wash, core and thinly slice apples. Layer in a lightly oiled 2-quart baking dish, alternating apples and yams. Sprinkle with spices and add orange juice. Cover and bake in a 350-degree oven for 1 hour, making sure it doesn't dry out. Add more orange juice if necessary.

One serving contains 190 calories, 2 grams of protein, a trace of fat, 45 grams carbohydates, 14 mg sodium, no added sugar, saturated fat or cholesterol. g PUMPKIN PIE (8 servings) 1 unbaked 9-inch pie shell made with oil 1 1/4 cups cooked or canned pumpkin 3/4 cup sugar 1/2 teaspoon salt 1/4 teaspoon freshly scraped ginger, or 1/2 teaspoon ground ginger 1 teaspoon cinnamon 1/4 teaspoon cloves 1 teaspoon flour 3 egg whites 1 cup evaporated milk 1 tablespoon water 1 teaspoon vanilla extract or 1/4 ounce vanilla bean

Preheat oven to 425 degrees. Combine filling ingredients and mix well. Pour into pie crust and bake for 45 to 50 minutes until a knife inserted near center comes out clean.

One serving of this pie contains: 210 calories, 4 grams protein, 8 grams fat, .28 grams carbohydrates, 230 mg sodium, 8 grams sugar, 45 mg cholesterol, 2 grams saturated fat. OLD TRADITIONAL MENU Butterball Turkey Bread Stuffing Gravy Candied Yams Green Vegetables Mashed Potatoes Cranberry Orange Relish Fresh Vegetable Relish Tray Parker House Rolls Salted Butter Pumpkin Pie Wine/Coffee/Tea NEW TRADITIONAL MENU Turkey Bread and Walnut Stuffing Gravy Fruited and Spiced Yams Broccoli with Lemon and Sweet Butter Homemade Mashed Potatoes or, Cranberry Orange Relish Fresh Vegetable Relish Tray Homemade Whole Wheat Raisin Bread Sweet Butter Homemade Pumpkin Pie Wine/Coffee/Tea or, Hot Cider with Cinnamon Sticks CAPTION: Picture, no caption; Reprinted from The Saturday Evening Post, Copyright (c) 1943, The Curtis Publishing Company; Chart, no caption