Most people don't realize that a huge amount of their basal metabolism goes into operating the brain. Just "keeping the lights on" in the average person account

Most people don't realize that a huge amount of their basal metabolism goes into operating the brain. Just "keeping the lights on" in the average person accounts for around 20% of your total daily energy expenditure! 6k cals/day is highly suspect, but anyone who has spent all day thinking hard can attest to how tiring it can be. That big brain of ours eats a lot of calories. The other thing is that stress causes the body to produce cortisol - the catabolic hormone which makes it easier for your body to break down tissue into energy. Naturally, this causes our body to respond with an instinct to take in energy. In many folks, this prompts overeating, which is why stress is often blamed for increases in fat, but if you don't adjust your diet at all, it can accelerate energy expenditure.