Is triple zero the dangerous new size?
No longer content with "size zero" or even "double zero", some celebrities are leading a dangerous new clothing obsession - the "triple zero".
"Triple zero" clothes are five sizes smaller than a UK 10. The 23-inch (58cm) waist that it demands is a healthy waist measurement for a six-to-eight year old British girl, reported Daily Mail.
Model Alexa Chung looking as thin as ever at a New York event last year.
For every Beyoncé or Kim Kardashian, there's a Kate Bosworth or Julie Bowen, sporting pencil-thin legs and protruding collarbones.
Modern Family star Bowen admitted she starved herself to fit into her dress at the Emmy Awards last year.
Julie Bowen (right) has shrank several sizes since her 2012 Emmy appearance (left).
Experts blame social media for the fad.
"The selfie craze in particular has intensified this, and celebrities know that if they post a picture of themselves looking skinny, with ribs on show, they’ll get attention," said A-list trainer James Duigan.
"But it isn’t always real - sometimes they’re breathing in and sometimes the angle makes them look thinner than they really are."
Hollywood A-lister Kate Bosworth in April this year.
There are no standardised guidelines between UK and US size charts, and this has led to the rise of "vanity sizing" to flatter women into buying, Grazia Daily reported.
So what are the health risks of being this underweight?
"Quite simply, being underweight is just as unhealthy as being overweight," nutritionist Dr Adam Carey told the Grazia Daily report.
"When you start to fall too far below (a healthy BMI) – as certain celebrities do – your body fat starts to reduce, which leads to irregular periods."
"Women need to produce the hormone oestrogen to protect their bone health, so being underweight puts you at a far greater risk of the brittle bone disease osteoporosis."
Source: Daily Mail, Grazia Daily