Why is it the calorie count of food, and not the mass, that determines weight gain?

Question

Why is it the calorie count of food, and not the mass, that determines weight gain?

In: 2

Answer 1

Food is full of energy, we measure that energy as calories. And if we get more calories than we need, our body stores rest as fat.

The trick is that food can weigh a lot, but not have a lot of calories. Food that has a lot of water in it, may weigh more and have greater mass, but our bodies can’t convert water into energy and store it as fat. And some food has a lot of fiber in it, which is something else that our body can’t easily digest and turn into energy.