By Dan Bilefsky

New York Times

LONDON >> The model in the Gucci ad is young and waiflike, her frail body draped in a geometric-pattern dress as she leans back in front of a wall painted with a tree branch that appears to mimic the angle of her silhouette.

On Wednesday, the Advertising Standards Authority of Britain ruled that the ad was “irresponsible” and that the model looked “unhealthily thin,” fanning a perennial debate in the fashion industry over when thin is too thin.

The regulator said that the way the woman in the image had posed elongated her torso and accentuated her waist, so that it appeared to be very small. It said her “somber facial expression and dark makeup, particularly around her eyes, made her face look gaunt.” It said the offending image — a still photograph of the model that appeared in an online video posted on the website of The Times of London in December — should not appear again in its current form.

The specific image was removed from the video on Gucci’s YouTube channel, though the model still appears in the ad directed by Glen Luchford.

The Italian fashion brand had defended the ad, saying it was part of a video that portrayed a dance party and that was aimed at an older and sophisticated audience. Nowhere in the ads were any models’ bones visible, it said, and they were all “toned and slim.” It noted that “it was, to some extent, a subjective issue as to whether a model looked unhealthily thin,” according to the authority.

The decision by the advertising authority, an independent industry regulatory group, barred Gucci from using the image in advertisements in Britain. The ruling comes amid a longstanding debate on both sides of the Atlantic about the perils of overly thin models projecting an unhealthy body image for women. As when critics lashed out against idealized images of “heroin chic” in the early 1990s, some have voiced concern that fashion houses are encouraging potentially hazardous behaviors by glamorizing models who are rail-thin.

Last year, the French parliament approved measures prohibiting modeling agencies from hiring dangerously thin models and requiring altered photographs of models to be clearly labeled. Under the law, models need a doctor’s certificate to certify they are fit to work, and employers could be jailed or fined 75,000 euros, or about $85,000, if the rules are breached.

The measures were intended to prevent young and vulnerable models from being pressed into becoming excessively thin, to protect against anorexia and to push back against images of unhealthily thin women featured in glossy fashion magazines.

At the time, some modeling agencies criticized the law, saying it was wrong to link the thinness of models to anorexia without looking at the full spectrum of symptoms. “It is very serious to conflate anorexia and the thinness of models,” Isabelle Saint-Félix, secretary-general of the National Union of Modeling Agencies, told Agence France-Presse at the time.

Last year, the Advertising Standards Authority ruled against an Yves Saint Laurent ad that featured a model with pipe cleaner-like legs lying on the floor. The authority said the model appeared “unhealthily underweight,” with a visible rib cage and very thin legs.

© 2016 The New York Times Company