For many dieters, that post-dinner period is the witching hour. They follow the program all day long, and watch what they eat. In fact, they've almost made it through the day when those P.M. cravings rear their ugly heads. An hour after you've finished supper and cleaned up the kitchen, it's far too easy to sneak back into the refrigerator or pantry and fall victim to a binge. Many experts believe that those midnight snacks wreak the most havoc on our bodies. A study conducted by Northwestern University discovered that the timing of your eating is every bit as important as what you eat. According to reports, researchers determined that mice who eat at weird hours gained twice as much weight. One suggested theory is that the body's internal clock plays a role as to how the body uses energy. In the study two groups of mice were given high-fat diets that they consumed at different times of the waking cycle.