Isabelle Caro, a French actress and model whose emaciated image appeared in an Italian ad campaign and whose anorexia was followed by other sufferers of eating disorders, has died aged 28.

Her acting instructor, Daniele Dubreuil-Prevot, said Caro died on 17 November after returning to France from a job in Tokyo. Dubreuil-Prevot said she did not know the cause of death but Caro "had been sick for a long time", referring to her anorexia.

Caro was featured in an ad campaign by the Italian photographer Oliviero Toscani in 2007 for an Italian fashion house. Under the headline "No Anorexia", images across newspapers and billboards showed Caro naked, vertebrae and facial bones protruding.

In later interviews, she said she had weighed about 27kg (about 59 pounds) when the photos were taken.

Caro said on her blog and in interviews that she had suffered from anorexia since she was 13. She wrote a book published in France in 2008 titled The Little Girl Who Didn't Want to Get Fat.

The ad campaign was launched at a time when the fashion industry was under scrutiny about anorexia, after a 21-year-old Brazilian model died from the eating disorder. Caro's agent, Sylvie Fabregon, said the image was intended "to show what it is like to be anorexic".

Some groups working with anorexics warned that it did a disservice to those afflicted. Images of Caro appeared on pro-anorexia websites; yesterday, one posted a notice about her death and a photo of her, with the caption "die young, stay pretty".

Caro spoke out about her anorexia and her efforts to recover, and the menace of eating disorders. Her acting instructor described years in and out of hospitals. Her illness and death "are an absolute waste", Dubreuil-Prevot said.

Caro's father alerted a few close friends at the time of her death, and a funeral service was held in Paris, according to Dubreuil-Prevot.