Someone who, at a party, always finds people walking away from them muttering " What a loser. Doesn't he have anything better to do?" after quoting useless and/or inaccurate statistics to make him look more interesting.
A person that uses their knowledge/feigned knowledge to make someone feel inferior for no other reason than to feel intellectually superior.
Everyone else at the party: "What a loser. He is so mentally obese that there should be a Richard Simmons work out tape dedicated to him."
2) A term given to people who only have food on their mind 24/7
2)John: Dude I´m dying for a cheaseburger.
Adam: Stop thinking about food! Your so Mentally Obese!