I'd never considered my preference for crunching as a stim. Learn something new everyday eh?
@Sportster - when you catch yourself grinding, rest your tongue between your front teeth. Relaxes your lower jaw a little. (Preventing head and neck ache)
Notice how you feel next time you do it.
It relaxes me and I feel more centred.
Once started the munching can get out of control though. I ate nothing but dried and chilled apricots for tea as I couldn't stop. You can get sulphite free ones which are much nicer and kind of black.