What is the effect of taking both metathione and iron supplement? Will iron inhibit or boost the effectivity of metathione? How much metathione should I need to take in a day? I'm 5'4" and 46kgs.

Are you using the metathione to whiten your skin? Or for the health benefits of glutathione? I don't see why the metathione would react with the iron in supplements any more than it would react with the iron in your own body.