Does regular peroxide really whiten teeth?

Yes, it does help. Just make sure you dilute it in water. I go with a 50/50 mix. If you look at the ingredients of most of the whitening mouthwashes hydrogen peroxide will be on the list.

That’d the same stuff that literally eats through rusty metal right?

I imagine it really works. I have yet to try it, but really want to…my teeth are too sensitive for commercial whiteners.

Yes, it will whiten teeth but be careful – it can also burn your mouth and tongue. I would definitely dilute it.

I used to dip my toothbrush in a cup of peroxide I was a teenager and didn’t know to dilute it and it really does work. The bad part was, it like foams up in your mouth where there is gunk, which made me gag horribly, but I had whiter teeth for it. Now if I were going to do it, I would dilute it, like johnpowell said.