Diets eaten by humans before industrialization provided more protein for each calorie consumed than the diets commonly eaten today.

This study says modern food has less protein per bite because it's full of sugar and fat, so we eat more to get enough protein. That means old-school diets, before all the processed food, probably had more protein in every calorie we ate.

Long ago, people ate more meat and eggs and fewer carbs; now we eat more bread and sugar and less meat. This study shows that our food today has less protein for each calorie, which might be why we’re getting fatter and shorter.