Mentally Obese
1) A term given to people who are very smart, and hold much knowledge.

2) A term given to people who only have food on their mind 24/7
1)Oh man, Sarah got another A+ on her calculus test, she is so mentally obese

2)John: Dude I´m dying for a cheaseburger.
Adam: Stop thinking about food! Your so Mentally Obese!