If you're looking for a low-calorie protein source, it's difficult to do much better than egg whites. Egg whites are a versatile food that you can use in baking or eat as an entree.
A half-cup of egg whites contains 63 calories and an incredible 13 grams protein. In contrast, it contains less than 1 gram of carbohydrate. A half-cup serving has a negligible amount of fat. You'll also get calcium, magnesium and potassium along with a smattering of B vitamins.
You can substitute egg white for whole eggs to make baked goods and entrees lower in fat. Melanie Jewkes, M.S., Utah State University Extension assistant professor, recommends substituting two egg whites for one whole egg. You can also use egg whites to make meringue and to add loft to souffles and baked goods.
Raw egg whites can lead to salmonella, a bacteria that can cause fever, severe diarrhea and dehydration. Avoid using raw egg whites in icings, salad dressings and other uncooked foods. Use egg white powder, which has been pasteurized, instead.