Many of the lifestyle changes you've already made (eating regular meals, cutting off eating two hours before bed, moving more) can help peel off the pounds, but to keep your weight loss going, or to maintain that loss, you'll have to start paying attention to portions. Knowing what an appropriate serving of carbs, fat, high-protein foods or other foods is can be tough thanks to all the extra-large, supersized products out there, but it's key to avoiding overdoing it at meals and snacks and keeping your calories in check.

Over the next several weeks, we'll be helping you figure out how many servings you should be eating of each. First, you learned about carbs (check out Choosing the Best Carbs and More Healthy Whole Grains for a refresher). Then you tackled fats (for more info, read The Facts on Fats and Get Your Fill of Healthy Fats).

For the next two weeks, you'll be focusing on protein. To learn why you need it, how many servings you should have and which sources are best, check out Protein Primer and The Leanest Proteins.