Lack of sleep throws your body’s hormone levels off balance which then impacts your hunger levels the next day. The 2 hormones that affect our appetite are ghrelin (the hormone that makes us feel hungry) and leptin (the hormone that makes us feel full). When we don’t get enough sleep, the level of ghrelin rises while our leptin levels drop. This causes you to feel hungry and overeat.
This may explain why the fat-burning effects of eating more protein were confirmed in a study published in the American Journal of Physiology. One group was fed a high-protein diet (just over 1 gram per pound of body weight per day) while the second group consumed an amount closer to the lower recommendation of the RDA (recommended dietary allowance). The group eating the higher-protein diet burned the most fat.