Bizarre (and dangerous) dieting fads through history - The diet industry is worth multiple billions of dollars. In the US alone, diet products and other weight-loss plans generate more than US$70 billion in revenue. Unsurprisingly, diet fads have been part of human existence for way longer than we care to admit. Throughout history, people have engaged in a myriad of dieting practices that have ranged from outrageous to outright fatal.

Browse the gallery and check out some of the bizarre dieting fads from history. You'll be shocked to know that a lot of them are still in practice today.

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Lord Byron's diet - When we think of a celebrity diet icon, we rarely (if ever) think of the 19th-century Romantic poet. But Lord Byron was obsessed with his weight.

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Lord Byron's diet -

The poet existed basically on biscuits and soda water or potatoes drenched in vinegar. He also wore several layers of wool to help him sweat off extra calories, as the BBC noted.

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The Inuit diet -

The early-20th century Icelandic-Canadian explorer Vilhjalmur Stefansson is credited with being an early advocate of what today would be called the keto diet, albeit Stefansson having practiced a more extreme version of the diet.

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The Inuit diet -

After coming in contact with native peoples during his Arctic explorations between 1908 and 1918, he became impressed with their protein-rich diets and began following it himself.

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The Inuit diet - Stefansson and a colleague spent four years in the Arctic eating just meat and fish as part of an experiment. In addition, the men advocated consumption of fatty meat, which they believed was an essential part of the diet. It sounds a lot like the keto diet, doesn't it?

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Chew and spit - At the turn of the 20th century, health food enthusiast Horace Fletcher pushed the notion that chewing food items until all the flavor had been extracted and spitting out the fibrous material was a quick way to lose weight.

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Chew and spit - This type of behavior today has been associated with eating disorders. CHSP, as it is often called, can be a disorder in and of itself, or it can accompany bulimia and/or anorexia.

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The original low-carb king - The 19th-century English funeral director William Banting is credited with being one of the early proponents of a weight-loss diet based on limiting the intake of carbohydrates, particularly the starchy and sugary kind.

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The original low-carb king -

In the early 1860s, Banting wrote a booklet called 'Letter on Corpulence, Addressed to the Public' in which he detailed the specifics of the diet.

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Tapeworm diet - In the early 1900s, women began to ingest pills packed full of tapeworms, a parasite that gets its nutrients for its host that often causes the patient to lose weight.

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Tapeworm diet - As bizarre as this fad may seem, it is incredibly alive and well. As Mic reports, it's still practiced today, with pills being sold illegally on the internet.

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Arsenic diet pills - Diet pills are nothing new. In the 19th century, pills that promised to shed the extra pounds quickly abounded, though they also poisoned the user.

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Arsenic diet pills - Many of the early diet pills contained arsenic and strychnine in their composition, both of which can kill in high doses.

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Diet to curb your impulses - The 19th-century evangelical minister Sylvester Graham (of graham cracker fame) preached that some foods stimulated sinful impulses, and thus promoted a bland diet that would curb the appetite, so to speak.

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Diet to curb your impulses - Graham advocated a diet based on whole-wheat flour and vegetarianism. He was also a proponent of using foods and diet as a way to maintain good health and fight off illnesses.

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Fat-washing soaps - In the 1920s, companies began to sell soaps that promised to wash away fat.

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Fat-washing soaps - One such product was the La-Mar Reducing Soap (not pictured), which promised: "No dieting or exercising. Be as slim as you wish," as the Daily Mail shows.

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The cigarette diet -

In the early 20th century, the cigarette brand Lucky Strikes began to encourage consumers to reach for a cigarette when they craved something sweet.

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The cigarette diet -

The use of nicotine as an appetite suppressant can actually be traced back to pre-Columbian peoples, who used it as a way to prevent hunger and thirst.

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The sherry diet -

In a 1955 article, Telegraph's columnist Barbara Taylor suggested that women finish off their meals with a glass of sherry.

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The sherry diet -

In her opinion, the fortified wine was a fail-safe addition to the "diet for Mrs Average."

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Calorie-restrictive diet - In the 16th century, Venetian nobleman and patron of arts Luigi Cornaro (painted here by Tintoretto) began to follow a calorie-restrictive diet, which he believed was the key to a long life.

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Calorie-restrictive diet - He restricted his diet to only 350 g (equivalent to the weight of two bananas) of food daily, including bread, egg yolk, meat, soup, and 414 ml of wine.

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Sleeping Beauty diet - The idea of sleeping to avoid hunger gained a lot of traction in the mid-20th century. One of its followers included none other than Elvis Presley. According to The Independent, Elvis once put himself in a coma in order to lose weight by being unconscious.

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Sleeping Beauty diet - While the fad has been around for decades, it is still practiced today and encouraged heavily in pro-anorexia blogs.

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Banana and skim milk diet - While the term superfoods seems to be a more recent phenomenon, the idea that certain foods have miraculous powers to boost one's metabolism has been around for at least a century.

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Banana and skim milk diet - At the turn of the 20th century, the United Fruit Co. embarked on a heavy advertising scheme that proposed that the fruit curative properties. Later, a doctor endorsed a diet based on bananas and skim milk, which he said would cure celiac disease.

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Prolinn shake - In the 1970s, a doctor named Roger Linn came up with a meal replacement called "Prolinn," which consisted mainly of ground animal horns, hooves, and other by-products, treated with artificial colors and flavors.

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Prolinn shake -

When 58 adherents had heart attacks, the FDA determined that “the diet was at least a contributing factor or a cause,” People magazine reported in 1977.

See also: Healthy eating habits from around the world

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