Listen up, carboholics! There's life beyond pasta and bread...and it could mean the difference between losing and gaining. Many people don't realize the importance of protein. However, protein is responsible for giving the metabolism a bigger boost than either carbs or fats. Consuming proteins like fish, chicken, eggs, milk, cheese and tofu enables the body to maintain and build muscle mass -- and the more muscle you have, the faster and better your metabolism functions. Add some sort of lean protein to every snack and meal to reap the benefits. When you load up on lean protein sources, researchers have found that you get full faster on less food. And when you couple a lean protein source and a high-fiber food, then you get a snack that keeps appetite at bay for a long time.