Under-16s are already banned at London Fashion Week
Models won't be forced to have health checks at London Fashion Week in September after other major cities refused to go along with the proposals.
The idea was recommended by the British Fashion Council after last year's size zero debate but it's already been ruled out in New York, Paris and Milan.
Officials in the three cities say forcing models to produce a medical certificate is too invasive.
Eating disorder charities are criticising the decision.
Size zero debate
Worries about underweight models started a couple of years ago when two South American models died from eating disorders.
In response, the British Fashion Council came out with 14 proposals last September in a report called the Model Health Inquiry.
One of the main suggestions was to introduce health certificates for models on Britain's catwalks.
But officials in New York, Paris and Milan didn't agree.
Catwalk models make up only 10% of the modelling population
They said the measures were unworkable and discriminated against other models who didn't appear on the catwalk.
But some people think the debate about weight is healthy and that the media are focusing on the wrong areas.
Karen Diamond is the director of Models One, the largest modelling agency in Europe.
She said: "The idea of a model health certificate is not a bad idea in itself, but it's just impossible to police and to govern.
"That's why it hasn't been implemented at this stage because there's just no way of doing it.
"Who's to say that a girl who gets this certificate, lets say it's valid for a year, isn't going to be OK in six months time or a year's time. You just don't know.
"The girls generally are not unhealthy."
Eating disorder charities aren't happy with the decision to drop the health certificate proposal.
They say fashion bosses are guilty of a U-turn and young models could become victims of conditions like anorexia.
Susan Ringwood from BEAT (Beating Eating Disorders) thinks models should be championing a healthy body image.
She said: "The British Fashion Council have stepped away from one of the fundamental recommendations of the Model Health Inquiry.
"Fashion is fantastic, it can be wonderful but there are some aspects of it that are still actually quite toxic."
Some of the inquiry's recommendations have already been put in to practice though.
They include banning under-16s from London Fashion Week catwalks and making sure that the shows have healthy backstage environments for models.