So, let me give you the basis for my opinion on “whole body” PEMF systems. I think the best place to start is with verifiable facts:
1 - Most people do not understand that the physics of magnetism is very different from the physics of light. Some people understand that light is propagated from a point source (ideal, but not realistic) as an “inverse square law”: if you measure the light intensity from two points where one point is twice as far away as the first point, then the light at the second point will be 1/4 the intensity of the light intensity at the closer point. That in English is “one over two squared times the initial intensity”.
That is the physics of light, it is essentially ultra simple and in a way “linear”.
If that confuses you, then keep in mind that magnetism is much much more complex than light. Magnetism does not radiate anywhere near like a “point source” radiator. It does not drop off at all by a simple “inverse square” law like light does. Magnetism drops off more like an inverse cube or inverse 4th power, so magnetism measured at the same two points as the light beam above would be only 1/8th to 1/16th the total intensity as the closer point.
RESULTING SCIENCE FACT: To fill as much volume of space with magnetism as you would with light takes many many times more energy.
An example of this is an MRI machine. With a massive magnet larger than a small swimming pool, cooled by liquid helium, and sucking down an average electrical power of 20 to 50 kilowatts, enough to power 2 to 5 average American homes, these machines generate huge magnetic fields right inside the coil, but the magnetic field drops off to almost undetectable levels within just a few feet. A mid-level MRI machine costs about $1M USD, not counting the costs to maintain and operate it. And even with all this, in no sense is an MRI machine a “whole body” magnet.
So, why should we think that there is any truth to the claims of PEMF marketers that their convenient pad is a “whole body” PEMF machine?
2 - If you cut one of these supposed “whole body” PEMF pads open, they typically reveal a copper coil with only about a 6 inch diameter effective area, placed into a pad of much greater size.
3 - I could verify this with email correspondence, but I will just tell you that basically none of the “whole body” PEMF systems actually have known, well-controlled output pulses. I know this because over the years many different PEMF manufacturers have asked me for help to measure and determine what their systems are actually doing. They are happy to make whatever claims will sell their products, but when tested, their claims are generally over-stated by a factor of 10x to 100x. This is widely known among PEMF marketers, but not widely discussed. Either you will believe me, or not, as you wish.
4 - Most people and clinicians will tell you that their PEMF system (any PEMF system) is very beneficial. Some of them have good clinical data to prove it. I think it is fair to say that most modern commercial PEMF systems really do benefit people quite a lot, especially when nothing else seems to help.
These are basic, verifiable facts plus some of my personal experience. My opinions are mostly based on these. Having looked at these things over the past 3 decades, I conclude that most of the modern PEMF products do give benefits to people, but not for the reasons the marketers claim. But with all of the needless false claims and disinformation in the PEMF marketing space, these things are almost impossible to discuss intelligently.
I think essentially all PEMF effects are localized within the body, then spread systemically as I discuss a few responses back, due to body fluid circulation and cell-signalling effects that spread from region to region in the body.
For example, when you sit on a “whole body” mat, basically you are applying a clinically effective dose of PEMF to your gluteus muscles and lower pelvis. This in turn leads to beneficial effects that can spread throughout the body, but will be most evident in the pelvic region and upper legs.
So, I conclude that basically most modern PEMF systems work, but that they work focally, not system wide, but they will eventually have system wide effects. Therefore the most honest way to describe the effects of PEMF is to describe them this way. This makes focal PEMF products inherently more honest than “whole body” PEMF systems, but not necessarily more biologically effective.