Re: fasting.. now yellow teeth?

I am a bit scared after reading that it has affected your teeth a little, my teeth are soooo white lol, I don't want the shade to change. Anyhow, I still plan on using toothpaste and I know some people frown on that idea but is it really that bad to use regular toothpaste during a fast? Or a herb toothpaste or hydrogen peroxide as mouthwash? I don't want to feel self-conscious while talking ha. I was thinking of using collagen lotion to see if it will fade my stretchmarks...is that bad too? Since it's been mentioned that anything you apply on the skin can seep in, so is that a bad thing...? Does water have to be distilled? Ok, I bombarded this thread, sorry. Anyone can answer these for me? Thanks!