hi, i do tht too sometime till my friends yell at me during movies or something.lol. i have done it for bout 2 years but wen i do i usually eat ice. most of the time its just ur body reacting to a craving u dont realize ur having. wen this happens, try eating hard candy or something crunch. ice and jawbreakers help. just brush ur teeth often if u choose to eat candy. tho ice is more healthy :) hope this helps
Chomping - do you mean "grinding" your teeth?
That would be from Stress.......frustration.......anger ........... or could just be a habit (like smoking) ...