Into a medium bowl, sift flour, baking soda, cinnamon and nutmeg. Set aside 2 tablespoons of the dry ingredients to toss with blueberries. Stirdry ingredients into creamed mixture.
Wash, drain, pat dry and flour blueberries. Fold into batter. Beat egg whites and gently fold egg into batter. Spoon into paper-lined or greased and floured muffin tins. Sprinkle brown sugar over each muffin. Bake at 375 degrees for 20 to 25 minutes.