When switched on, the electrodes rapidly rust in a chemical process called electrolysis which quickly turns the water brown.

[2][3] Detoxification foot baths consist of two major components, a simple container in which to place the feet and an electrode array.

[5] Effects like "re-balancing the cellular energy" of the body, helping with headaches and sleeplessness, to kidney, liver and immune system function are regularly stated.

At each spa they visited, they were told that the treatments would improve their overall health, and that the change in the color of the water was due to the release of toxins from their bodies.

Inside Edition then purchased their own detox foot bath and had it examined by electrical engineer Steve Fowler, at his lab.

With that information, he decided to have his water samples tested for creatinine and urea, two of the smallest breakdown molecules that the human body creates.

After trying the apparatus and getting the brown residue even when the bath is running without the presence of human feet, Timothy Caulfield concluded that "this is a really good example of what's ultimately nothing but a marketing scam.