Sleeping your way to weight loss sounds like a gimmick, but there is a correlation between how much sleep you get and how lean you are. One study shows that lack of sleep disturbs metabolic and hormonal process, increasing hunger and making it harder to drop those extra pounds. Lack of sleep seems to decrease the amount of leptin, a hormone that is thought to decrease appetite -- less leptin meant more hunger. Another study showed the less people slept, the more they weighed. It's also easy to overeat when you're tired and trying to rustle up the energy to make it through the day. That sleepy, groggy feeling can complicate all your daily routines. You can improve your sleep habits with a little discipline. Breaking the late-night TV habit and simply turning in earlier can go a long way.