Comment by irthomasthomas
3 years ago
My examples demonstrate that calories in / calories out is false. I don't quite get your point? A calorie is a measure of the useful energy released from burning stuff in a furnace. It was invented to compare the efficiency of different fuels for steam engines. It has no relevance to humans, who don't use a furnace and steam power, but a complex chain of cascading chemical reactions.
What I mean is that "calories in" is not literally calculated by the total energy you put in your mouth, but rather the energy your body absorbs from that. And as you note that might be different based on the food, how the food is prepared, content of the food, etc.
Likewise "calories out" is not literally calculated by adding up your movement & exercise. We know that things like hormonal levels, etc can all impact how much energy your body is expending.