Skeptics are well aware of a few of the more popular doctors selling woo on the web or on TV. One of the them, Dr. Mercola, is mentioned many over and over for his anti-vaccine stance and his pseudoscientific approach to medicine. In fact, Josh DeWald just caught Dr. Mercola misrepresenting dental fillings just over a week ago. Today, Dr. Mercola tweeted about his interest in “grounding aka earthing” and its “benefits.” What drives me crazy about the information in the link he tweeted is not just that he is misrepresenting the health benefits, but he makes it more difficult to undo his misrepresentation of how electricity works in a basic physics sense.
There is some science in the article he gets right. There is a section where he discusses AC and DC currents that, although incomplete, is a pretty good and accurate description of how things work. Although they don’t explain how the drift velocity cited for the flashlight example in this section was obtained, it isn’t unreasonable, and in fact is something many people don’t know about electricity. When we think of electricity, we think of it “flowing,” so it is interesting to note how slow the electrons actually “flow.”
Other than that section, the science turns to pseudoscience and misinformation quickly. The main claim in the article is that somehow, evolution intended us to walk barefoot on the Earth, and that such a process causes electrons from the Earth to enter your body where your immune system can somehow use them. It further claims these electrons protect your body from inflammation. Aside from the gross misrepresentation of the role of electrons in your body, Dr. Mercola claims the effects are well-studied without actually linking to any of the studies making this claim – well other than saying “Do you notice you feel better when you walk barefoot on the Earth?”
One of the most egregious errors is the representation of electromagnetic fields. Here’s an example of an illustration (which is really just a claim, but somehow it is supposed to make things clear):
…a variety of devices introduce spikes or transients that distort the 60 cycle electric field in the wiring, particularly when appliances are switched on or off.
To illustrate this phenomenon, we will use the example of your neighbor’s refrigerator or air conditioner switching on or off. This produces a sudden electrical “spike” that travels through the power lines to your household electrical system. A signal is also radiated into the atmosphere because the wiring acts as an antenna. Taken together the various signals and distortions to the alternating current field create what some people refer to as “dirty electricity.” Attempts have been made to link these phenomena to a variety of health effects. There has been considerable debate about this issue.
I’m not sure what point is being made. To me, the term “spike” would indicate some kind of increase. If anything, the local grid being stressed by several high power appliances would temporarily decrease the current. You can sometimes see this in your home when your own air conditioner cycles on. It depends on many factors. It does cause a measurable change in the voltage you read at an outlet in your home, but claiming this is somehow “dirty” is nonsense.
The other thing they get wrong is “A signal is also radiated into the atmosphere because the wiring acts like an antenna.” There are two possibilities here. One is the possibility of the wire producing an electromagnetic wave, which isn’t dependent on the atmosphere, and in fact the atmosphere would attenuate any such signal. At 60 Hz, the wavelength of such a wave would be about
500 5,000 kilometers, which is much too long to ever expect it to interact with the body. The second possibility is a magnetic field, which for decades people have tried to connect with various diseases. Assuming a very high current draw of an air conditioner of 30 amps, the magnetic field at 5 meters away would be about 0.012 Guass—which is about 2% of what we are exposed to 24 hours a day from the Earth’s magnetic field. If a magnetic field of that strength causes disease, the Earth is doing it to us and not any electrical device.
Another claim is that “alternating electric fields are present everywhere in the environment—they are radiated from wires, even when no current is flowing through them.” I can’t even begin to imagine how they came up with such a claim. Well, I guess I can come up with some far fetched explanations and maybe find a way to make this true. Even in those cases, the effect would be so small that it would take some pretty sensitive measurements to do so, far smaller than the background radiation naturally produced by the sun (something Dr. Mercola constantly touts as being healthy).
Embedded at the top of the article is a video in which Dr. Mercola and Clint Ober try to explain how all of this works and then demonstrate why you need to buy their expensive grounding equipment. In one demonstration, Clint puts an electrode on Dr. Mercola and then displays a voltmeter reading about 1 volt of potential on the doctor. Clint then has Dr. Mercola place his hand on the grounding pad, and the voltage goes to about 0.02 volts (which Clint even misreads and/or exaggerates as two thousandths instead of two hundredths). This is a total sham demonstration; if you look at the setup, the other wire of the voltmeter is hooked up to the grounding pad. This would be like putting both wires of a voltmeter on the same side of a battery—of course it is going to read zero.
One thing Dr. Mercola didn’t think through in writing this article is he explains how electrons are the particles being moved in electricity, and then claims those same electrons will protect you from various electric fields. If your body has more free electrons, those electrons can then easily be moved by an electric field. So in a sense, your body would be more susceptible to an electric field, and you could actually induce a current in your body as you walk through electric fields.
Dr. Mercola’s question “Do you notice you feel better when you walk barefoot on the Earth,” seems to stem from Clint Ober’s website statement where he says “Go barefoot outside for a half-hour and see what a difference it makes on your pain or stress level.” As David Gorski points out, “Can you say ‘placebo effects’? Sure, I knew you could.” Of course a half-hour break walking on the grass on a warm day away from the stress of the work day is going to make a person feel better. I can say with certainty it has nothing to do with electrons at my feet. It has much more to do with the electrons already present in my brain.
If someone really feels they need extra electrons, just go ahead and shuffle your feet across a carpet for a minute or so. That little shock you get from touching the doorknob? That’s because you picked up a few too many electrons. You will pick up all the electrons you need from your normal interactions with the environment. You don’t need special treatments to protect you from this mythical “dirty” electricity. I imagine your health would be better if you simply stopped worrying about it. It would also help my health as I wouldn’t have to un-teach bad physics.