A government minister is the latest to warn people of the dangers of fad diets, but people have been following them for centuries. Why?
As early as the Greeks and Romans people have been dieting. But while it was largely about health and fitness back then, it's the Victorians who really kick started the fad diet.
"The Greek word diatia, from which our word diet derives, described a whole way of life," says Louise Foxcroft, a historian and author of Calories and Corsets: A History of Dieting Over 2,000 Years.
"Dieting back then was about all-round mental and physical health. People really got a taste for fad dieting in the 19th Century. It is during this time that things tip over into dieting more for aesthetic reasons and the diet industry explodes."
So what are the weirdest and unhealthiest fad diets from history?
Chew and spit
At the turn of the 20th Century the American, Horace Fletcher, decided a lot of chewing and spitting was the way to lose weight.
Fletcherism, as it was called, promoted chewing a mouthful of food until all "goodness" was extracted, then spitting out the fibrous material that was left.
He was fairly prescriptive in how many times you had to chew different foods. Just one shallot needed to be chewed 700 times.
It was hugely popular and had some famous followers, including Henry James and Franz Kafka.
It got to a point where people were timed at dinner parties to make sure they were chewing enough, says Foxcroft.
"The diet also meant only defecating once every two weeks and it was nearly odourless, described by Fletcher as smelling like 'warm biscuits'," she says.
"Fletcher carried a sample of his own faeces around with him to illustrate this wonder."
Not for the squeamish, in the early 1900s the tapeworm diet started to be advertised, says Foxcroft. Many years later the opera singer Maria Callas was reported to have eaten the parasites to try and lose weight, but it's since been suggested that this was the stuff of myth.
Dieters would swallow beef tapeworm cysts, usually in the form of a pill. The theory was that the tapeworms would reach maturity in the intestines and absorb food. This could cause weight loss, along with diarrhoea and vomiting.
Once a person reached their desired weight they then took an anti-parasitic pill which, they hoped, would kill off the tapeworms. The dieter would then have to excrete the tapeworm, which could cause abdominal and rectal complications.
It was risky in many ways. Not only can a tapeworm grow up to 30 feet (9m) in length, they can also cause many illnesses including headaches, eye problems, meningitis, epilepsy and dementia.
"During the 19th Century dieting became big business," says food historian Annie Gray. "Advertising was becoming more and more sophisticated, with more and more diet products being peddled."
The diet industry boom was also down to the rise in celebrity and the media and the development of new medicines, says Foxcroft.
Diet drugs, pills and potions became increasingly big business in the 19th Century. But these so-called "wonder-remedies" often had dangerous ingredients, including arsenic and strychnine.
"It was advertised as speeding up the metabolism, much like amphetamines do," says Foxcroft.
While the amount of arsenic in the pills was small, it was still extremely dangerous. Often dieters would take more than the recommended dose of the pills thinking they would lose more weight, risking arsenic poisoning .
Also, arsenic was occasionally not advertised as an ingredient meaning people didn't know what they were actually taking.
"Such poisons were loosely controlled then and easily obtained for all sorts of household and medicinal purposes," says Foxcroft.
"Charlatans set themselves up as experts with diets to promote and products to sell. Plenty of people bought into these 'miracle cures'."
Celebrity dieters are nothing new. Lord Byron was one of first diet icons and helped kick start the public's obsession with how celebrities lose weight.
Much like today people wanted to look like celebrities of the time and new diet fads were advertised in the expanding media.
And like today's celebrities, Byron worked hard to maintain his figure. In the early 1800s the poet popularised a diet consisting mainly of vinegar.
If he were alive today he would probably be endorsing a book about the diet - and it would probably be a bestseller.
In order to cleanse and purge his body he would drink vinegar daily and eat potatoes soaked in the stuff. Side effects included vomiting and diarrhoea.
Because of Byron's huge cultural influence, there was a lot of worry about the effect his dieting was having on the youth of the day.
Romantics were restricting themselves to vinegar and rice to get Byron's fashionably thin and pale look.
"Our young ladies live all their growing girlhood in semi-starvation," wrote one critic at the time.
During this time eating patterns became more prescriptive, with set dining styles, says Gray.
"This also caused people to worry about their size. Queen Victoria was terrified of putting on weight."
In the mid 1800s Charles Goodyear figured out how to improve rubber beyond its natural state with a process called vulcanization.
With the Industrial Revolution and mass production, suddenly the use of rubber expanded massively.
That included rubber knickers and corsets. The thinking behind both was that rubber held in fat but more importantly caused sweating, hopefully leading to weight loss.
They were worn by both men and women, says Foxcroft. It wasn't much fun as the skin-macerating underwear meant flesh would be softened and broken down by extended exposure to moisture, making it vulnerable to infection.
"At the time all sorts of gadgets and treatments were being advertised as the way to lose weight," says Gray.
It was World War I that curbed the fad, with rubber being needed for the war effort.