I broke the fingernail habit way back when I started on analogs, so switching to vaping didn't make a huge difference there..but where it has made a difference, I'm no longer chewing gum or snacking on food all the time. If you ask me it just boils down to an oral fixation of some type or another, whether it's nail-biting, snacking, smoking/vaping, teeth grinding (haven't done that since I picked up vaping!), etc.