A small study from Purdue University found that when participants followed a high-protein weight-loss plan (1.5g of protein per kilogram of body weight) for a few weeks, they not only lost weight, they also reported better-quality sleep than those who had less dietary protein. “Dieting may leave you feeling hungry in the middle of the night. The higher protein may provide the satisfaction and blood-sugar stabilization necessary to prevent this midnight wake-up call,” explains Lyssie Lakatos, R.D., a nutritionist not involved in the study. Even if you’re not trying to lose weight, a small snack with protein and carbs (like Greek yogurt with fruit or peanut butter on whole-grain crackers) can help stabilize blood sugar and boost brain chemicals that cause sleepiness.