Stim treatments: if they can’t hurt, they probably can’t help either

• Apr 2, 2020 • by Paul Ingraham

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Photograph of a hand illuminated on a black background by criss-crossed streaks of deep red light.

Red & infrared radiation on a hand in an infrared scanner. Photo by Yu Chieh Ho.

I recently tackled the topic of far infrared saunas, which was long overdue. You can read my take on them in my thermotherapy article. It was the last major topic in a set of “healing ray” topics I’ve written about, which are all based on the exciting idea that just the right kind of energetic stimulation is going to cause human cells to work better somehow. This optimism underlies various ultrasound modalities, cold laser therapy, electrical stimulation, and even just coarse physical vibrations. (It’s also closely related to several types of allegedly “regenerative” therapies as well, like platelet-rich plasma, prolotherapy, autologous chondrocyte implantation, and stem cell therapies — they all depend on the idea that, given the right stimulus, cells will respond with something great.)

All these ideas are mostly sustained by seeming advanced/technological … and by absence of anything obviously illogical or impossible about any of them. Biology is full of surprises, after all. But that doesn’t mean that any of it is actually likely to work. Our physiology is heavily optimized by evolution, and it doesn’t make a habit of keeping tricks up its sleeve until it is tickled by a specific form of radiation. What would be the survival advantage of a healing power that can only be activated by laser light? Salamanders have remarkable regenerative powers… which are “stimulated” by amputations, not far infrared saunas.

And with great power comes great responsibility, because that which has real potential to help also has the potential to do some damage. We cannot be optimistic about the potential for helpful effects without also embracing the possibility of harmful ones. To hope for one is to admit that it could also backfire.

This is a basic fact of medicine that is not just missing from all the brochures for saunas and laser gadgets, but also from most of the endlessly “preliminary” and “promising” scientific papers (most of which aren’t fit to line a birdcage).

And now we flip this principle inside out: to the extent that any exotic form of bio-stimulation is actually safe — as infrared radiation appears to be, for instance — it is also medically uninteresting.

This logic applies to many other kinds of treatments as well, of course. I wrote about the double-edged sword of benefit/harm in this context because I think there’s a bigger and stranger blind-spot for the potential harm of treatments based on exotic biology/biophysics. But it definitely also applies, for instance, to a lot of “natural” remedies, or indeed practically anything “alternative.”