We are biologically hardwired, aren’t we, to want more food, always more? The failures of our massive efforts in dieting away the pounds are proof. Aren’t they? Look again. If anything, the human digestive system is designed to maximize our ability to move, not our ability to take in food.

Think about it. Humans stand upright. As a result of our upright posture, we have a mobility that is rare among animals. We do not hibernate. Our transformation from infant to adult does not involve a cocoon or chrysalis stage. We are constantly moving. We are not the fastest or strongest. We are not the most agile or deft. What characterizes our movement is its novelty: we are constantly learning to make new movements, new patterns of sensing and responding that guide us in thinking, feeling, and acting. As a result of this ability, we have proven ourselves capable of finding food and making ourselves at home in nearly every climate on earth.

At every point, our digestive system enables us in making these movements. Our manner of processing what we consume provides us with a steady stream of energy so that we can keep moving. We do not eat one meal a week and sleep it off like other carnivores. Nor do we spend a third of every day grazing like the large herbivores. Instead we move through recurring cycles of hunger and fullness over a 24-hour period. We stomach small, dense meals, mostly cooked, preferably several a day. These rhythms of digestion allow us time between meals to hunt, gather, and grow food, while still providing us with the steady stream of nourishment we need in order to do so. Even when we are in a position to eat more energy than we are burning, we store it all over the body, in patterns that, until we are extremely obese, maximize our ability to keep moving. We eat to keep moving so that we can eat to keep moving from environment to environment, season to season, continent to continent, meal to meal. And in order to move, we must stop eating.