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Juil Shoes make shoes that have copper buttons in the sole "connecting" the wearer to the earth. The claim from their website:
"Free radicals" occur in our bodies when we are exposed to toxins, pesticides, and generally anything that is toxic to our tissue (now-a-days, its more things than not). Over time, free radicals build up in our bodies. In order for them to become stable, the radicals must find an electron to "connect" themselves to. Where are these electrons then? Beyond the sources found in certain foods, vitamins, etc, we have an abundant source of electrons right beneath us in the earth. If we fail to connect ourselves with these sources, radicals attack our healthy tissue to rob the cells of their electrons. The result? A high potential for infection and inflammation, among other ailments.
Dr. Carol Davis (Professor Emerita – University of Miami Miller School of Medicine)
Well, it turns out that our earth's surface carries a natural, bountiful source of electrons that our bodies also need. These electrons have a balancing effect on our nervous systems and quench free radicals as well. Essentially, when we connect directly with the earth's surface, electrons rising from its soil or sand will enter our bodies and turn the "negatives" we build up day-to-day into "positives."
Dr. Daniel Chong (Naturopathic Doctor)
So the claim appears to be that staying connected to the earth reduces the number of free radicals in our body, and furthermore this reduction of free radicals leads to better health.
Looking at this piece from Steven Novella:
Cell metabolism in part creates oxygen free radicals which are molecules that steal electrons from other molecules, causing a cascade of reactions that can damage proteins and other chemicals in the body. Anti-oxidants are chemicals that can stop free radicals and limit the damage. They therefore decrease “oxidative stress” on cells. So far it sounds like anti-oxidants are therefore a good thing and we should be gobbling up as much as we can. However – free radicals and anti-oxidants exist in cells in a homeostasis. Free radicals are used by the immune system, for example, to fight invading organisms. They are also important signaling molecules, triggering other cell-protective mechanisms.
Therefore, taking large amounts of anti-oxidants and disrupting this normal balance may not necessarily be a good thing. I’m not saying it’s necessarily a bad thing, we just don’t know. You cannot extrapolate from pre-clinical data – essentially looking at what happens to various molecules and cell functions – to clinical claims. The role of free radicals and anti-oxidants in the body is too complex for us to extrapolate to net clinical effects. At best the existing data might suggest the potential for a clinical effect, but in order to know we would have to do properly designed clinical studies.
It appears that free radicals are not well understood, and a lot of research still needs to be done to fully understand them.
If we trust Steven Novella we can assume the second claim of reducing free radicals provides health benefits is not based on current scientific knowledge.
So is there any research that shows being in direct contact with the Earth (or any electrically grounding surface I guess) reduces the number of free radicals in our bodies?