Calories In & Out theory is WRONG! (Well, Partially); and our approach to optimal weight achievement

Calories in & Calories out is a model based on Physics

1 Calorie is the amount of heat required at a pressure of 1 standard atmosphere to raise the temperature of 1 gram of water 1° Celsius from 14.5° to 15.5° C—equal to 4.1855 joules.

Our body however, does not have any receptors of calories per se. Moreover, our body have different hormonal responses to different foods.

Yes, 1 Calorie from soda, and 1 calorie from broccoli is the same. But the way body absorbs and processes it is different

An easier explanation:

https://www.youtube.com/watch?v=wKEP_Z6u-L0