Eli5:What prevents our bodies to get rid of excess food/calories that are not necessary, and instead turns it into fat?

Question

Eli5:What prevents our bodies to get rid of excess food/calories that are not necessary, and instead turns it into fat?

In: 55

Answer 1

Your body has no way of knowing that it is excess calories that are not needed. We evolved in a state where starvation was an almost constant threat. As such it stores excess calories as fat for use when food is not available.