Does fasting rid the body of toxins?

Dear Cecil: A fairly sophisticated colleague just completed a five-day water fast, something he does two-three times a year to “purge his body of toxins.” A Harvard-educated client of mine keeps going on fruit-juice-based fasts — again to purge the toxins. And an old friend from grad school is now engaged in a very expensive round of “chelation” to push the toxins out of her body. Me? I’ve always thought that this is what we have a liver and two kidneys for. So, here are my questions: (1) What the heck are these toxins anyway? (2) Can they be measured? (3) Where do they come from? (4) How do we get rid of them? Thomas B. Siegman, New York, New York

Cecil replies:

Oh, there are lots of toxins. Ethanol, now. Toss back a shooter or six at your brother’s bachelor party and chances are next morning you won’t be saying, Whoa, it’s great to be alive. Nicotine’s another. Ozone, carbon monoxide, and other compounds derived from auto exhaust. Fat in foods isn’t a toxin in the strict sense, but consume it in excess and from the standpoint of long-term health effects you’re slowly poisoning yourself.

As soon as you begin to list toxins, however, it’s obvious the detox regimens you describe aren’t apt to be much good at getting rid of them. Better you should stop smoking, eat and drink less (and exercise more), and quit driving that SUV. But how much fun is that? It’s more entertaining to spend a few days and sometimes a pile of money on a water fast, an herbal diet, chelation or “ayurvedic” therapy, or some other form of new-agey hokum, after which you can resume your wicked ways.

Some will object: It’s not the known toxins I’m worried about, it’s the ones that sneak up on you. You know the rap — thousands of chemicals have been introduced into the environment in the past century with little or no testing; it isn’t so much any one poison as the accumulation of poisons that will kill you; etc. Never mind that the question of low-level effects remains controversial, that we haven’t seen any big die-offs locally (in contrast, Russia and many eastern European countries have seen marked declines in life expectancy due to environmental factors in a much broader sense, e.g., alcoholism), and that the experts, to the extent they’re willing to guess, generally attribute red-flag indicators of ill health such as cancer to obvious causes like smoking.

The thing is, even if we concede for the sake of argument that obscure toxins are a threat, there’s no reason to think that detox therapies offer any protection. Examples:

Chelation. This therapy involves intravenous infusion of the chemical disodium EDTA, which binds to metallic ions in the body (including heavy metals) and allows them to be excreted. Early experiments suggested that chelation dissolved the calcium in arterial plaque and reduced hardening of the arteries and other circulatory problems. Subsequent research has largely failed to replicate these results, and the current consensus is that chelation is effectively snake oil. Not only is it expensive, it depletes your body of the metals you want to keep, too, including important micronutrients such as zinc.
Fasts and herbal diets. Lots of variation here, but the idea generally is to stop eating whatever you’ve been eating (or anyway cut back) and heavy up on water, juice, herbs, or some other holistic Drano that will flush the bad stuff out of your system. Abrupt changes in diet are always a little dicey; I came across one account of a kid who gave himself serotonin syndrome (confusion, tremors, fever, etc) after downing tryptophan and St. John’s wort to detox himself from ecstasy, a therapy he’d seen recommended online. I suspect this kind of thing is rare and that most diets and fasts won’t harm you if you keep them up for only a short time, and of course a balanced low-cal diet coupled with exercise and stuck to long-term can have major benefits. But the notion that you can somehow purge toxins for a few days and be done with it is for the birds.
Ayurvedic medicine. Popularized by Deepak Chopra, ayurvedic medicine grew out of transcendental meditation (remember the Maharishi?). There’s more to it than detoxification, but herbal diets, purification, and so on are part of the mix. No proven benefit, although I imagine positive cash flow has increased Chopra’s personal sense of well-being.
Colonic irrigation/colon cleansing. Trendy names for the good old enema. What next, bloodletting?

In short, you’re quite right — the human body has its own highly evolved mechanisms for eliminating toxins that, under normal circumstances, you don’t need to enhance with anything more elaborate than indoor plumbing and a good magazine. By the same token, if you’re overtaxing your liver and kidneys, you don’t need a water diet, you need to rethink your life.

Cecil Adams

Send questions to Cecil via cecil@straightdope.com.