Is it bad Doctor ?

This morning I met my doctor :

- And how's your throat ?

- oh, ok, no angina since a couple of weeks but let me ask you : can you see part of my tongue is black. Can you cure this ? Is it bad ?

- ....

- What ? did I say anything wrong ? is it that bad ? (and suddenly I saw myself without tongue in my mouth, not that I'm using it a lot but still can be useful)

- you drink too much red wine.

- ...

- It's OK, you're french.

- Well fine, maybe you're right I drink often red wine, but still any advice ?

- Try white wine !

I definitely must find me another doctor.