Heat oven to 400°. Fill muffin pan with 12 paper muffin baking cups or grease each muffin cup with butter or butter-flavored spray oil. Using a meat mallet or rolling pin, crush bran cereal in a plastic food-storage bag.
In a bowl, stir together egg whites, oil and yogurt. Add cereal, flour, brown sugar, baking soda and salt; stir until dry ingredients are moistened. Gently stir in berries. Fill each muffin cup about 3/4 full.
Bake 18-20 minutes or until golden brown. Remove from pan immediately.