What really got me started on this was a chart at the local gym around 2011. The chart posted next to the leg press machine said that if you are 213 lbs (my weight at that time) you HAVE to be taking in a minimum of 3,500 calories per day to maintain that weight. I questioned the Gym owner/personal trainer about this. I told him at that time I had not eaten much over 1,800 calories daily in almost a year. (School, work, life stuff in the way) and just like the ass holes here and elsewhere his reply was "Oh, you just don't know how to calculate your calories"
Calculating calories is not rocket science. The body is far more complex than that. See the post by test above. And thats only a small part of it. To believe 3,000 calories of pizza and beer will have the same effect on weight as 3,000 calories of boiled chicken breast is fucking retarded.
Breakfast this morning: Coffee, donut, (340 calories) two bowls of coco pebbles (4cups 560 calories) Total 900 calories. Used 2% milk