Kirstie Clements, the ex-editor of Vogue, has released a book that reveals the dark side of the fashion world, with shocking secrets like models eating tissue paper to stay thin.

Kirstie Clements was fired last May from the position of editor of the fashion bible Vogue. Clements had served the magazine for 25 years. Now, she has released a tell-it-all book titled "The Vogue Factor" that reveals the dark side of the fashion industry, bringing out in the open shocking facts about what models do to keep themselves in shape.

The book states that models eat tissue paper to curb hunger pangs and to keep thin. She has also discussed how eating disorders are rampant in modeling. "That's the insidious part of eating disorders," Clements told ET.

Clements has insisted that the book is "larger than just skinny models."

"(It) has a lot of truths about what happens in fashion publishing. It's an honest account of what goes on," she concluded.

She also reveals that there are different measures of thinness in the fashion world. "When a model who was getting good work in Australia starved herself down two sizes in order to be cast in the overseas shows... the Vogue fashion office would say she'd become 'Paris thin'."

According to a report on the book in the International Business Times, a Russian model told the author that her flat mate was a "fit model" - meaning that she was extremely thin. As a result of avoiding solid food, she was "in hospital on a drip a lot of the time".

Another shocking revelation is that editors often have to edit models to make them look less emaciated, getting rid of bones so that they appear less thin.