THESE COOKIES HAVE gone on a diet. Margarine has replaced the butter, and egg whites have replaced the whole egg.

Lemon Yogurt Cookies

1/2 cup margarine, softened

1 1/4 cups sugar

1/2 cup plain nonfat yogurt

2 egg whites

1 tablespoon grated lemon peel

1/2 teaspoon vanilla

2 cups quick oats, uncooked

1 1/2 cups all-purpose flour

1 teaspoon baking powder

1/2 teaspoon baking soda

1/4 cup powdered sugar

Heat oven to 375 degrees.

Spray cookie sheet with no-stick cooking spray. Beat margarine and sugar until fluffy. Add yogurt, egg whites, lemon peel and vanilla; mix well.

Gradually add other ingredients except powdered sugar; mix well. Cover and refrigerate for about one hour. Shape dough into one-inch balls. Place on baking sheet. Using bottom of glass dipped in sugar, press into one-eighth-inch thick circles.

Bake 10 minutes or until lightly browned. Cool two minutes; remove to wire rack. Sift with powdered sugar. Cool completely. Store tightly covered.

Makes 48 cookies. Each cookie has 70 calories, 2 grams fat, 1 gram protein, 13 grams carbohydrate, 0 cholesterol and 45 milligrams sodium.