Ghrelin and Leptin are 2 hormones that are important for a healthy metabolism. Ghrelin is the hormone that tells you when to eat, while leptin is the hormone that tells you to stop eating and when you are sleep deprived, you have less leptin and more ghrelin and thus you tend to overeat. According to the American Journal of Clinical Nutrition if a person takes sufficient sleep then his resting energy expenditure—the amount of calories burned when you’re not moving is five percent higher than their tired counterparts.