inFact with Brian Dunning inFact with Brian Dunning


Cleansing Diets

It seems nearly all your friends are doing special cleansing diets. Should you do one too?

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Cleansing diets are a food fad that's been around for decades, from the Hollywood 48-Hour Miracle Diet, to lemon & maple syrup concoctions, to today's absurdly overpriced high-sugar fruit smoothie drinks that you buy an in impressively multi-colored, day-specific pack.

Notice that accredited healthcare providers like medical doctors and dietitians never recommend that you buy these cleansing products — they recommend the most basic (and free) health advice of all: eat right and get some exercise. It's only the unaccredited, unlicensed tradespeople like nutritionists and yoga teachers who will advise you to buy cleansing products — and not surprisingly, will often sell them to you themselves.

Why don't doctors advise cleansing for general health? Because there is no such thing in medical or dietetic science. The idea that toxic substances from a normal diet build up in your body and cause health problems is a fantasy invented by marketers. Proof: Humans and animals all exist fine, and have for millions of years, without these products. We have perfectly functioning systems already built in: kidneys and livers. The technical medical terms for detoxification are "poop" and "pee".

Make no mistake: These are nothing more than trendy snake oil products that use sciencey-sounding language to take advantage of gullible people who have disposable income.

A lot of disposable income. In the United States alone, high-end boutique cleansing juices are a $60 billion industry. The main demographic is healthy, educated, young women — exactly the same target demographic as high end fashion and cosmetics. Make no mistake. Cleansing is a trendy fashion statement; it's got nothing to do with your health.

That's why the marketing claims are medically meaningless: "ridding the body of toxins" without ever identifying what these alleged toxins might be; or "boosting the immune system", which if it were medically possible, would mean giving you an autoimmune disease, where your body's overactive immune system begins attacking your own normal healthy cells.

This is a change in diet that you're going to do for a week at most, so it's not going to affect your overall long-term health in the slightest. But if you really want to, or if you just want to go on a one-week weight-loss binge, don't throw your money away. Have yourself a couple pieces of fruit and a multivitamin each day, and you're getting a virtually identical fast for next to nothing.

— Brian Dunning

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References & Further Reading

Editors. "Nothing Tastes as Good as Skinny Feels." Bloomberg Businessweek. Bloomberg LP, 18 Feb. 2011. Web. 2 Nov. 2012. <>

Editors. "How Glycolysis Works." Anatomy & Physiology. McGraw-Hill Companies, 4 Nov. 2008. Web. 2 Nov. 2012. <>

Miller, B. "How Crash Diets, Like the Master Cleanse, Harm Your Health and Heart." Health. Health Media Ventures, 22 Jun. 2009. Web. 3 Nov. 2012. <,,20409933_1,00.html>

Moore, S. "Health Risks of the Master Cleanse Diet." Livestrong. Demand Media, 26 Apr. 2011. Web. 3 Nov. 2012. <>

Moores, S. "Experts Warn of Detox Diet Dangers." NBC News., 18 May 2007. Web. 3 Nov. 2012. <>

Wohaieb, S., Godin, D. "Starvation-Related Alterations in Free Radical Tissue Defense Mechanisms in Rats." Diabetes. 1 Feb. 1987, Volume 36, Number 2: 169-173.


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