I have an ionizer near my bed too. People used to laugh at me for thinking oxygen and skin are related. I say to them, scientific proof is easy for this one:
Just look at the faces of smokers. Look what happens to people who stop smoking.
Anyway, I like cigars but now they are rare.
The ionizer for sleeping is cool. Watch the EMF though. The one I have has a little motor/ionizer and emits high EMF (skin blotcher in itself:) So, I face it towards the wall.