You may have heard of the Jawbone, Fitbit, Nike Fuelband, or one of the myriad of other wearable self-tracking gadgets. You might even be wearing one right now! These gadgets help track everything from hours slept, calories consumed, to number of steps taken in a given day. But, can they actually make you healthy? Sure they provide us with tons of data about our bodies, but what do we do with all that information? Is it just about the knowing? Or does this actually motivate us to change and enhance our behavior? And if it does, can that be a bad thing?