Step into any supplement shop and head on over to the protein section, and you'll likely be faced with the same thing no matter where you are - a wall of whey. Whey protein seems to have cornered the market as far as bodybuilders are concerned, prized for its high bioavailability, rapid absorption, and convenient, powdered form. However, whey isn't the only way to go - there are plenty of other powdered protein sources, such as egg and soy, the latter of which may, according to recent research, be preferable to whey, despite what supplement store shelves might indicate.