I've been getting questions from patients on the validity of ionic foot baths again. They are a scam and I'm embarrassed by practitioners charging money for these sessions. It amounts to a very expensive foot soak.
In 2011 they were all the craze, some of my colleagues purchased them and started offering them as a treatment and I was on the fence about their validity. So I asked my chemistry professor at the University of Minnesota what he thought. He was unfamiliar with the device but he said it didn't make sense to him because molecules just don't travel through the body like that--they have to go through a transport system such as the lymph, blood, or into the urine. You simply don't get molecules traveling through your body to your feet and out your skin. Even sweat has to follow prescribed metabolic pathways.
I tried one out when a colleague offered me a session. There is a piece of metal in the water and one adds salt and an electric current. Of course the water changes color—it's called rust! That's what happens when you oxidize metal. That will happen regardless of anything else placed in the water. We did a similar experiment in chemistry lab (no feet involved).
The death knell on the subject was when I watched this series of videos on YouTube. A highlight is when an organic carrot produces a color change that indicates it is releasing liver toxins.
There are places where faith, belief, and the concept of energy as a miasma are appropriate. The field of chemistry is not one of them.