We’re thinking about calories all wrong.

The importance of gross-calories versus net-calories.

We all know what calories are. We see the calorie labels on food and know that we put calories in our bodies when we put food in our mouths. And we all know that we burn calories when we exercise. Our Apples Watches and FitBits tell us so.

You may also know the “calories in, calories out” principle. This principle says that we gain weight when the calories we put in our bodies (eating) are greater than the calories we use (exercise). And conversely, we lose weight when the calories in are less than the calories out.

But it’s a little more complicated than that. There’s only one way to put calories into our bodies — by eating. But it turns out there are lots of ways that calories get used and leave our bodies. And exercise is one of the smallest and least significant of all these ways. (This is why it’s incredibly difficult to exercise your way out of a poor diet.) All of our bodily functions require a lot of energy and burn lots of calories — thinking, pumping blood, regulating body temperature, building and repairing muscles, and a host of other activities.

One of those bodily functions that requires energy and burns calories is digesting food. That’s right — it takes calories to break down and digest food…