The idea that the body is filled with pollutants that can be expelled by a severely restricted diet and detox supplements is not supported by science. Photo: Getty
''I'm going on a detox," a friend said recently. Her plan was to cut out alcohol, caffeine and processed food, and live off a mix of fruit and vegetables, mainly as juice, and a cache of herbal supplements that promised to cleanse her body of toxins.
When I asked what "toxins" she wanted to expel, this friend, like most other people I've asked, was stuck for an answer.
People have been detoxing their bodies for centuries. The historical treatment of bloodletting was based on the theory it could rid the body of "overabundances" that cause disease.
These days, most detoxing involves a severely restrictive diet, often with the assistance of any number of "detox in a box" kits that line the shelves of chemists, supermarkets and beauty stores.
These products make promises like – "helps the body cleanse itself of toxins and pollutants caused by the excesses of a busy life" and "cleanse your system and whisk away the polluting nasties".
And my favourite, a product that says it can "help neutralise nasty free radicals, which can cause damage to your body's cells".
The idea that the body is filled with pollutants that can be expelled by a severely restricted diet and detox supplements is not supported by science.
The above phrases are pseudo-science nonsense, designed to baffle consumers and make them think these products' claims are based on science. Products often have celebrity testimonials, another sure sign there's no evidence to support the claim.
Yes, chemicals can enter the body via the food we eat, the air we breathe and the drugs we ingest. But the body – specifically the lungs, kidneys, liver, gastrointestinal tract and immune system – is designed to neutralise nasties and remove waste.
It was difficult to find any large and recent peer-reviewed studies that had tested the claims of detox kits. But a group of early-career scientists, part of the group the Voice of Young Science, published a "detox dossier" that reviewed a bunch of popular detox products in 2009.
They found none of the product manufacturers were able to provide evidence for their kits' claims, or even give a comprehensive definition of what they meant by "detox".
"We concluded that 'detox' as used in product marketing is a myth," they said.
"Many of the claims about how the body works were wrong and some were even dangerous."
Australia's consumer watchdog Choice came to a similar conclusion in their review of detox kits in 2005. They suggest consumers save their money.
"Detox supplements provide little or no known benefit over a healthy diet."
"A week or two on a detox program won't absolve you from a year of unhealthy eating, smoking or drinking too much alcohol."