Yep. I worked with a fat guy who claimed he only ate 1500 kcals a day. I routinely saw him eat 1800 kcal breakfasts and 2000+ kcal lunches. I am sure dinner was much more than that. And the thing is, he sincerely believed he was eating only 1500 kcals per day.

People can be really, really deep into self-delusion. Nearly everything everyone reports about how much food they consume is a lie — and especially the obese.