The idea of “toxins” is usually used as a tactic to scare people into buying de-toxifying snake oil of one sort or another. It’s not that there’s no such thing as a poisonous substance — obviously there are dangerous substances in the environment and in biology. The problem is with the kind of people who toss the idea around, and the reasons they do it: fear! profit! ignorance! And the total lack of any specific claim or scientific knowledge or evidence to support it.
It is so vague that it’s effectively meaningless and useless for anything but marketing.
But it’s very good at that! Indeed, “detoxification” may be the single most common marketing buzzword in alternative health care (“boosting” the immune system is a tough competitor).
But exactly which toxins we’re talking about, or exactly how they are disposed of, is never explained by anyone selling a product that supposedly detoxifies — because they just don’t know. Their ignorance of the actual biology of toxicity is profound, an epic fail.
Alt-med aficionados are almost intentionally vague when discussing toxins. To them, it seems, toxins are either all-purpose nasty substances without specific identities or substances whose toxicity appears not to depend upon dose. In the former case, toxins might as well be miasmas. If you’ll recall, the miasma theory of disease stated that infectious diseases were caused by a “miasma”; i.e., “bad air.” This was not an unreasonable concept before the germ theory of disease, because before germ theory the agents through which infectious disease was transmitted were unknown, but it’s not so reasonable now. Alternatively, “toxins” often seem to function like evil humors in the humoral theory of disease. Either way, alt-med toxins do not correspond to anything resembling toxins or toxicants in science.
~ Fashionably toxic, Gorski (ScienceBasedMedicine.org)
The real deal: what poisons and toxins actually are
There are real toxins, of course. It’s just fine to talk about toxins in the correct context. Example:
Q. Hm, I wonder if it’s safe to eat this potato salad that’s been sitting out in the sun for 5 hours?
A. Noooo, it’s probably overflowing with botulinum toxin!
A poison is literally any harmful substance, and even something safe in typical doses becomes a poison in overdose (so you can be poisoned by either lots of water or a minuscule amount of lead). Toxins are technically poisons produced by living things, like venom or metabolic wastes, but informally the word is synonymous with poison.
There’s a staggering variety of poisons/toxins, but the two major categories that most people imagine purging are pollutants and metabolic “wastes”
Pollutants are probably what most people hope to purge. The best specific candidates would be the persistent organic pollutants like pesticides, flame retardants, and polychlorinated biphenyls (PCBs, now banned, but formerly ubiquitous in many plastics). Lead is also an alarmingly common environmental poison (and much in the news lately). All of these are indeed found in our environment and our bodies, where they mostly get trapped in fat and otherwise sequestered. We definitely would like to get rid these, if only we could!
Metabolic by-products or “wastes” is a much murkier category, because many of them aren’t “wastes” at all. That is, in practice, most metabolic wastes do not behave as toxins. Cellular chemistry produces a lot of molecules, with many fates. Technically these are toxins because some metabolic by-products are indeed poisons (harmful substances) and they are produced by a living thing (by definition)… but context is king, and they are also normal products of biology, and so most of them are either safely excreted, or actually re-used and re-cycled.1 As in the rest of nature, not much in cellular chemistry is wasted. Lactic acid is the ultimate example: misunderstood for decades, even by many people who should know better, lactic acid isn’t a persistent waste product and you wouldn’t want to “flush” it or “suck” it out of your muscles even if you could.
While some people are busy trying to detoxify, others are using toxins in controlled doses to paralyze their facial muscles. Sometimes the same people try to do both!
There are real toxins, but real detoxification is not up to you
The body protects itself from dangerous molecules in a few ways. It eliminates some and recycles others; some are trapped in a safe place; and quite a few can’t be safely handled by the body at all (metals, for instance).
“Sweating it out” is one of the oldest ideas about detoxification, and perhaps the silliest. Sweating is for cooling, not taking out the trash — it’s not a significant excretory pathway.2
No one has ever cured anything but stress in a steam room. A sweat lodge has never saved anyone from any kind of poisoning.
Ionic attraction is another great example of a fake detoxification mechanism. This awful idea is most widely known from “ionic foot baths,” one of the scammiest of all snake oils. Ionic bonding is electrostatic stickiness, the atomic scale equivalent of rubbing a balloon and then sticking it to your hair. It doesn’t reach out and grab things like a tractor beam, let alone across a multicellular structure like a sweat gland; it’s more like velcro, bonds forming only when ions actually touch each other. Even if sweat glands did squirt out toxins, ionic attraction can’t help out by reaching across the gland any more than a charged balloon is going to scoot all the way across a room to get to your hair. Sweat glands are a lot bigger than ions. To an ion, a gland might as well be a giant train station.
Epsom salts supposedly detoxify. It’s completely unclear how. Something about osmosis mumble mumble. Which makes exactly no sense. See Does Epsom Salt Work?.
Detoxifying diets and “cleanses,” foods, and supplements are another extremely popular category — and such a large, diverse category that it’s hard to sum up. Suffice it to say, genuine nutrition and supplement experts are sick to death of all of it. See Examine.com’s main toxin page.
There are of course literally dozens of other claims about detoxification. But the only truly “detoxifying” treatments help the body eliminate or disarm molecules the body cannot actually process on its own … and it’s not a DIY thing. For instance, a stomach pump for someone with alcohol poisoning is literally “detoxifying.” So are chelation for heavy metals, and antivenoms. The list of true detox treatments is short. They often involves poisoning emergencies, and they are idiosyncratic to the specific biology of the problem.
Related reading … and lots of it
This is just a little topic primer. Detoxification is only slightly relevant to pain and therapies for pain. For more detailed and referenced information about toxins and detoxification, I’ll refer you to other articles. For instance, I’ve written lots about the relationship between massage and detoxification:
- The popular notion of “flushing” toxins with water in Why Drink Water After Massage? Massage is groovy for all kinds of reasons — it doesn’t need the support of the idea that it detoxifies.
- On the contrary, there is some reason to believe that brutally deep massage may actually be toxifying — the interesting problem of rhabdomyolsis and post-massage soreness & malaise (PMSM).
- Finally, in my general massage science article, I have a thousand words or so on massage as a detoxifying detoxification treatment in general, and the myth of lactic acid removal in particular.
For more general consumer advocacy and education about toxins, see:
- Wikipedia has a dry but good page on detoxification, of course.
- WebMD has a much more readable article about detox dieting. It sets a seductively open-minded tone — as if they are going to help you choose a detox diet — but then they drop the skepti-hammer: “If your goal is to detox your system, don’t waste your time or money. Your body is an expert at getting rid of toxins no matter what you eat.” Yep.
- Most major media outlets have published warnings about detox scams: The Guardian, ABC News, NPR, CBC (particularly awesome), and many more.
- This was probably the first article on this topic ever published online, and still available: “Detoxification” Schemes and Scams (from QuackWatch.org).
- Notable articles on toxins and detoxification from Science-Based Medicine include:
- The Detox Scam: How to spot it, and how to avoid it
- Ask the (Science-Based) Pharmacist: What are the benefits of coffee enemas? (incidentally, this is one of the most popular articles SBM has ever published)
- You’ve done a detox. Now what?
- Dr. Gorski’s excellent post (quoted above), Fashionably toxic
- Even Mercola.com, a site that notoriously endorses all manner of quackery, thinks 'Detoxifying' Foot Pads are a Scam!
- Here’s a nice summary of another common example of toxin fear-mongering: mercury in amalgam fillings, plus a supplemental treatment of Dr. Oz’s take on amalgam.
- You’ve done a detox. Now what?
About Paul Ingraham
I am a science writer in Vancouver, Canada. I was a Registered Massage Therapist for a decade and the assistant editor of ScienceBasedMedicine.org for several years. I’ve had many injuries as a runner and ultimate player, and I’ve been a chronic pain patient myself since 2015. Full bio. See you on Facebook or Twitter.
What’s new in this article?
2018 — Added much more information about real poisons and toxins, plus more specific debunking of some popular detox concepts (sweating it out, ionic foot baths, and Epsom salts).
2012 — Publication.
- Metabolic wastes aren’t generally considered an example of toxins. Including them here is a bit of a rhetorical setup for explaining that they aren’t actually functionally toxic in the human body. If a toxin is consistently safely handled, is it still a toxin? This could get philosophical! Classification/taxonomy always get funky when you try to get serious about them.
- Imbeault P, Ravanelli N, Chevrier J. Can POPs be substantially popped out through sweat? Environ Int. 2018 Feb;111:131–132. PubMed #29197670 ❐ Good quality reporting on this study from National Geographic: “Fact or Fiction: Can You Really Sweat Out Toxins?”