The body is well capable of getting rid of toxins - that's what the liver, lungs, kidneys and skin do. So what's the point of detoxing?
If celebrities such as Carol Vorderman are to be believed, a detox diet can be a life-changing experience.
It can reportedly help people lose weight, beat cellulite, banish bloating and make your skin glow.
The theory behind the diet is that bodies are continually overloaded with toxins, which build up in a person's system and cause problems.
Clearing the system by detoxing promises all kinds of results and is now a multi-million pound industry, with products and supplements to help expel unwanted toxins. But making dietary changes is at the core of most.
'Meaningless'
The foods allowed and banned can vary widely, but generally fruit, vegetables, beans, nuts, seeds, herbal teas and massive amounts of water are allowed.
In contrast, wheat, dairy, meat, fish, eggs, caffeine, alcohol, salt, sugar and processed foods - most of the foods that many people love - are banned.
But if our body is already designed to expel waste, what is the point of detoxing? There isn't any point, according to new research, which says the body can recover from the excesses of Christmas on its own.
WHO, WHAT, WHY?
"The detox fad - or fads, as there are many methods - is an example of the capacity of people to believe in and pay for magic despite the lack of any sound evidence," says Martin Wiseman, visiting professor of human nutrition at the University of Southampton.
Most of the pills, juices, teas and oils that are sold for their detoxifying effects on the body have no scientific foundation for their claims, according to the research. People would be better off drinking tap water and having an early night.
The British Dietetic Association says detox diets are marketing myths rather than nutritional reality.
"Detox is a meaningless term that is used all the time and because it hasn't been defined, it's impossible to say if it has worked or if it hasn't," says a spokesman.
'Empty promises'
"The body is set up to deal with the chemicals it doesn't want, and excrete them."
HAVE YOUR SAY
Scientists and dieticians argue that the benefits people feel are not due to their body getting rid of excessive toxins but are due to changing from what is likely to have been a "poor" diet.
Fewer headaches, for example, is probably the result of being fully hydrated due to drinking so much water and better skin may be due to eating more antioxidant-packed fruit and vegetables.
Dr Rob Hicks, who writes for the BBC's health website, says another misconception of detox diets is that fruits and vegetables are low in toxins while meat and fish lead to the accumulation of harmful substances in the body.
He says the opposite is often true; vegetables such as cabbage and onions are high in naturally occurring toxins, while meat and fish often have low levels.
Detoxing can actually be dangerous for groups such as teenagers or pregnant women, who cannot afford to deprive themselves of food groups.
But some health experts say detoxing does have its benefits and can improve people's diets.
Independent fitness consultant Jane Gray says like any diet, detoxing should be done sensibly.
"Following a detox can help change people's bad eating habits and re-educate them about food. As long as they still have a varied diet, eat enough and get all the required nutrients, it can help improve people's health.
^ Back to top | BBC Sport Home | BBC Homepage | Contact us | Help | ©