A law in France, which bans featuring extremely thin fashion models, has come into effect, the media reported.
According to the law that came into effect on Friday, models will need to provide a doctor's certificate attesting to their overall physical health, with special regard to their body mass index (BMI), a measure of weight in relation to height, the BBC reported.
The Health Ministry says the aim of the law is to fight eating disorders and inaccessible ideals of beauty.
Digitally altered photos will also have to be labelled and images where a model's appearance has been manipulated will need to be marked "photographie retouchee" (retouched photograph).
Employers breaking the law could face fines of up to 75,000 euros ($82,000) and up to six months in jail.
France is not the first country to legislate on underweight models - Italy, Spain and Israel have all done so. Anorexia affects between 30,000 to 40,000 people in France, 90 per cent women, according to health ministry figures.