Answer:
I am the kind of soda you must not drink. What am I?
I am rarely touched but often held. If you are smart you'll use me well. What am I?
Use me if you really want to see inside someone
I'm not really more than holes tied to more holes; I'm strong as good steel, though not as stiff as a pole.
I am the place to turn when nature calls.
No matter how little or how much you use me, you change me every month.