You may hear people say that all calories are the same...
Well they are WRONG!! Different calorie sources can have vastly different effects on hunger, hormones, energy expenditure and the brain regions that control food intake.
When it comes to your body, things are not that simple. The human body is a highly complex biochemical system with elaborate processes that regulate energy balance.
Different foods go through different biochemical pathways, some of which are inefficient and cause energy (calories) to be lost as heat.