Detox diets are just another weight loss wonder, says Flinders University's Head of Human Physiology, Professor Simon Brookes.
With Christmas fast approaching – one of the busiest times on the social calendar – Professor Brookes warns that quick-fix detox drinks and liver-cleaning potions will do little to flush toxins from the body after weeks of overindulging on festive fare.
"Whenever I hear the word detox the word rubbish springs to mind," Professor Brookes says.
"Our kidneys, liver and gastrointestinal tract are all designed to remove or neutralise toxins within hours of them being ingested.
"So the idea that you can somehow supplement this with some miracle powder, or some miracle drink, is nonsense."
And the more expensive the product is to buy, the more people are likely to believe it works, Professor Brookes says.
"It's the placebo effect, people will actually believe it works if it costs more and has a horrible taste because they think it must be good for you.
"The marketing ploy is that it will make you feel better so you start to think you do feel better but it's basically helping your conscience, not your body."
Despite their shortcomings, Professor Brookes says detox diets are not entirely useless because they may encourage people to adopt healthier habits.
"You should be having lots of fresh fruit and vegetables and you shouldn't be eating junk food all the time so if a detox diet gets you off those things, that's well and good.
"But the idea that a two-day or two-week detox is going to fix all your problems after years of a bad diet, well, that's a fantasy."
While it may be the "same old message", Professor Brookes says the key to good health is to follow a balanced diet, exercise regularly and get plenty of sleep.
"It's all common sense – eat healthy foods, drink lots of water, get the heart-rate up and steer clear of too much alcohol and cigarettes – these things are all obvious but people don't want to hear it because it's the same old message but it's really the answer that works.
"There's no point turning to a detox for a quick-fix, just look after yourself in the first place."
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