PARIS, France — Labels from Givenchy to Saint Laurent showed of their new designs at Paris Fashion Week, alongside another innovation meant to wean the industry off its association with unhealthily thin, underage models.

All said they were honouring a new charter by their parent companies LVMH and Kering, setting age and size-limits for the people parading their clothes - a timely development say campaigners, who want it to spread even further.

"I've seen a lot of girls have eating disorders ... (the charter) helps them from harming their bodies to fit the standard," said model Danielle Ellesworth, 20, as she prepared for Christian Dior's show.

Two years ago, Dior, part of LVMH, made waves by picking a 14-year-old for the catwalk - the new charter only allows people older than 16 to display adult clothes.

LVMH and Kering will also no longer use models below the French size 34 for women and 44 for men, meaning the United States' infamous "size 0" — equivalent to a French 32 — is out.

It is still far from an industry-wide standard, and the models in Paris remained very slender and young — the stars included Kaia Gerber, the 16-year-old daughter of supermodel Cindy Crawford, who modelled for Kering's Saint Laurent.

But designers, models and other insiders said it was a start that could encourage people to denounce bad practices.

"It's important that this industry takes responsibility," said British designer Stella McCartney, after showcasing a contrasting collection of cotton T-shirts and bright taffeta skirts at Paris' baroque Opera Garnier on Monday.

"The houses must, the designers must, the casting directors must, the agents must, the models must," added McCartney, whose eponymous label is part of Kering.

Cyril Brule, founder of Viva Model Management and the head of a French union for modelling agencies, said the companies' all-encompassing ban could be more effective than regulations and laws brought in by individual countries.

"Something had to be done," Brule said. "Things had gradually deteriorated, there were more and more instances of depression, of models suffering panic attacks."

There has been some resistance and some designers have defended the use of tall, thin models as the best way to show off their creations. Karl Lagerfeld, creative director at privately-held Chanel, hit out in a 2009 interview at the "fat mummies" objecting to thinner women.

Dior designer Maria Grazia Chiuri said there were also technical considerations - her teams found it easier to work upwards from smaller-sized dummies and prototypes, whether on shoes, hats or clothes.

"There are some sizes that are good for making the first prototype," she said after unveiling her collection last week.

But some other brands have already started to push beyond the charter. Issey Miyake, part of Japan's Shiseido Group, used three models over 40 in a dance-filled runway show on Friday.

"I didn't want to stick to one particular kind of muse," said the brand's designer Yoshiyuki Miyamae.

By Johnny Cotton and Sarah White, with additional reporting from Pascale Denis and Noemie Olive; Editor: Andrew Heavens