The Evolution of Diet nationalgeographic.com

<blockquote>cooking not only gave early humans the energy they needed to build bigger brains but also helped them get more calories from food so that they could gain weight. In the modern context the flip side of his hypothesis is that we may be victims of our own success. We have gotten so good at processing foods that for the first time in human evolution, many humans are getting more calories than they burn in a day. “Rough breads have given way to Twinkies, apples to apple juice,” he writes. “We need to become more aware of the calorie-raising consequences of a highly processed diet.”</blockquote>