In terms of digestion, there is something called the thermic effect of food. Remember how every process in your body requires energy? Digestion is no different. Every food you eat requires some energy to break it down, absorb it, and put it to use or store for later. Protein has a high thermic effect, which means it burns quite a few calories simply from digesting it—roughly 20–30 percent of the calories in a solid protein will be burned from digesting it, and that number is closer to 5–10 percent for most carbs and fats. You shouldn’t try to adjust the total calorie content based on this, but it’s good to know. The more solid proteins you eat, the more calories you’ll burn simply from digestion.