I have a terrible chewing problem-- It just happens. When I'm sitting, minding my own business, I find myself chewing on my pencil. I've tried chewing gum to replace pencil/thumb/hair chewing, but I'm just a monster when it comes to gum-- As soon as it's in my mouth, It's gone. I suppose these are two separate problems, but I'm describing gum chewing as my failed solution.

Is there any way I can get rid of my terrible chewing habit?