Detox diets and cleanses are quite popular these days, especially if you’re of the Goop-y persuasion. And while they might seem to make sense on an intuitive level, from a science perspective, is there anything to actually back that up?
Commercial detox products tend to refer vaguely to “toxins” without actually specifying what those toxins are or the mechanism by which their detox product would help in removing them. There’s also no evidence showing that these undefined toxins are present in particular amounts.
Proponents of these types of detoxes often dichotomize chemicals/compounds are either fully good or fully bad. Yet all of us are exposed to a wide variety of chemical substances, both natural and synthetic, that range from harmful and helpful, often depending on dose/amount.
I’ll pause here for a detour to a bit of a side rant. Sometimes the word “chemical” is used as though it’s a 4-letter word. But what is a chemical, exactly? Wikipedia describes a chemical substance as “a form of matter having constant chemical composition and characteristic properties.” Good old water, H20, is a chemical. Oxygen (O2) is a chemical. Salt (NaCl) that you sprinkle on your food is a chemical. Chemical is not a bad word. Okay, end of rant.
How the body deals with toxic substances
The body has many ways of getting rid of things that it doesn’t want. The liver, kidneys, gastrointestinal system, skin, and lungs can all join the party. Sometimes removal is a multi-pronged approach; for example, the liver may change the form of a compound to something that the kidneys are then able to excrete.
Bioaccumulation can occur when the body stores a substance in areas from which it’s harder to get rid of things. Whether this occurs depends on the characteristics of the individual substance, like whether it’s water or fat-soluble.
There’s a wide range of different detox approaches, including fasting, selectively eating only certain types of food, and selectively avoiding certain foods. Non-dietary approaches include chelation therapy, use of saunas, ear candling, and colon cleanses.
While certain compounds have been shown to help remove harmful metals in animal studies, it’s unclear if that’s relevant to humans at the amounts that we’re typically exposed to. Research in humans just doesn’t seem to have happened.
Yet detoxes sound like a good idea if you don’t think about any of the nuts and bolts. That reasonableness on an intuitive level has made companies in the alternative health industry some serious dollars. Because who needs proof something works if your mind a) thinks it should work, and b) wants it to work. With generally low levels of scientific literacy, pseudoscience may even be more palatable to the general populace than actual science.
Pronounceability ≠ toxicity
“If you can’t say it, don’t eat it” was advice given by In Defense of Food author Michael Pollan in an interview with NPR. In Defense of Food made some very good points, but this particular bit of advice feeds into the idea of indiscriminately dichotomizing substances as good or bad.
I remember reading something quite a while back (I don’t recall the source) claiming that the inclusion of cyanacobalamin was a problem because it was along name that was hard to pronounce. The author had failed to look up cyanacobalamin’s more pronounceable name, vitamin B12.
Dr. Edzard Ernst, director of complementary medicine at University of Exeter and Plymouth has challenged the validity of alternative detox (as opposed to medical detox, e.g. from alcohol). He argued that for alternative detox hasn’t addressed basic scientific questions like what exactly the “toxins’ are, how they’re quantified, and it’s determined what patients require detox treatment. He pointed out that it would be very easy to demonstrate the effectiveness of this kind of detox if it did actually work; one would need to simply test the levels of the toxin in question, administer the detox, and then retest. If it works, why isn’t there already mountains of evidence?
Ernst also blasted a “detox tincture” made by Prince Charles’ company Duchy Originals (not to be confused with the perhaps more apt douchy originals). In an article published on Quackwatch, he wrote that “Prince Charles and his advisors seem to ignore science and prefer to rely on ‘make believe’ and superstition.”
If Prince Charles and Gwyneth Paltrow are proclaiming the health benefits of something that the head of a complementary medicine department at a major university is saying is quacky, I’m taking the quacky side.
- Cohen, M. (2007). ‘Detox’: science or sales pitch? Australian family physician, 36(12), 1009.
- Ernst, E. (2012). Alternative detox. British medical bulletin, 101(1), 33-38.
- Ernst, E. (2009). Some Notes on Prince Charles’s Duchy Originals Detox Tincture. Quackwatch.
- Klein, A. V., & Kiat, H. (2015). Detox diets for toxin elimination and weight management: a critical review of the evidence. Journal of human nutrition and dietetics, 28(6), 675-686.
- Wikipedia: Chemical substance
- Wikipedia: Detoxification (alternative medicine)
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