Off in on since kindergarten I've had the nasty habit of biting my nails. I don't know what causes it, it just happens. When I was younger it was just biting the nail portion, but as I got older it got worse. Now, I bite the skin, and bite so much at the skin around the nail, it bleeds.

I've been trying to kick the habit, and I don't even know if its caused by something. My fingers are always red, and lately I've begun to gnaw away at the skin on the knuckle of my thumb. It's really disgusting, I know, but I don't even know what causes it.

Any suggestions?