I am pretty confident that I can predict how I am going to feel after a big meal: snoozy, sluggish and definitely full. But by lunchtime the next day I am sure I will find room for another roast. When you think about it, it is pretty weird that the day after an enormous meal we can eat exactly the same quantity again. Did we not learn our lesson the first time?

Why do we still feel hungry after feasts like Thanksgiving or Christmas? Does overeating “stretch” your stomach, meaning you have more room for food the following day? Even thinking about it now is making me hungry.

The answer is, for most people, you don’t feel hungry in spite of the huge quantities of food you’ve recently consumed. You feel hungry precisely because of it.

But first, what is this sensation of hunger? The pang you feel that urges you to eat is the result of a number of physiological changes inside your body.