The LA Times reports that ionic foot baths may be relaxing, but claims of detoxification 'make zero sense." According to Steve Gilbert, an affiliate associate professor of environmental and occupational health sciences at the University of Washington in Seattle, "there's simply no way to draw large amounts of chemicals, toxic or otherwise, through skin. 'The skin is a darn good barrier that's designed to keep things in the body. [Claiming to pull] stuff across that barrier is nutty.'
Different companies have different explanations for how ionic foot baths supposedly work. Ionicfootbath.com explains that the 'negative ions produced by the ionic detox . . . create a gentle vibration that aids the release of unwanted toxin particles through the pores on the sole of the foot.' The site says that the foot bath is especially helpful for removing heavy metals and 'chemicals.' The ionSpa site says that an electric current in the water floods the body with 'negative hydrogen ions' that neutralize free radicals.
The assertion that negative hydrogen ions -- hydrogen atoms with an extra electron -- can clean up free radicals in the body is unfounded, says Nuran Ercal, professor of chemistry at the Missouri University of Science and Technology in Rolla. 'I've been studying free radicals for 25 years, and I've never heard of this. A lot of the things [these companies] are saying are very wrong. I'm stunned.'
The voltages used in water baths are almost certainly too low to break apart water molecules, added Andrew Barron, chairman of chemistry and professor of materials science at Rice University in Houston. Even if they did, the resulting hydrogen ions would have a positive charge, not a negative charge as some companies claim. A good thing too, because negative hydrogen ions are so highly reactive that they would badly burn a person's feet, he says.
Barron recently tested the water from an ionic foot bath after a 30-minute session. The water was murky, but it didn't show any traces of heavy metals or industrial chemicals other than a few chunks of rust that may have flaked off the electrodes. 'If there was a way to pull that through the skin, I'd be shocked,' he says. 'They're saying things that sound good, but they have absolutely no validity on this planet.'