It's likely that this delicious snack is already a staple in your diet, but it would be wrong to leave it off this list. Non-fat Greek yogurt is creamy, decadent, and amazing for your body. On average, one eight-ounce serving offers up nearly 20 grams of muscle-feeding protein. You can eat it plain if you like, but the beauty of Greek yogurt lies in its versatility. From fresh fruit, to seeds and nuts, to honey or cinnamon, your add-in options are endless.