Fashion models in France will have to show they are a healthy weight to end the "glorification of anorexia".
Under a new law, they will need a doctor's certificate to stop super-skinny models working in advertising or on the catwalk.
Magazines must also label any images which have used computer technology to change a model's shape.
Fashion bosses and models face a six-month prison sentence or fines of up to £50,000 for featuring underweight women.
MPs have ruled that doctors must decide if a model is healthy by taking into account her age, gender and body shape. If satisfied she is not too thin, they will issue the medical certificate.
A bid to impose a minimum body mass index - a measure of body fat based on height and weight - was dropped after protests by the fashion industry.
The tough rules were proposed by Socialist MP and neurologist Olivier Veran. He said: "It is intolerable to promote malnutrition or glorify anorexia and to commercially exploit people who are endangering their own health."
Veteran Italian designer Giorgio Armani supports the move. He has said the fashion industry must recognise "the link between its preference for abnormally thin models and the growth in eating disorders in young women".
- Daily Mail