The organizers of Spain's top annual fashion show on Sunday rejected five out of 69 fashion models as being too skinny to appear in this year's event, acting on a decision to bar extremely thin women from the catwalk.

The show, known as the Pasarela Cibeles, decided in September not to allow women below a body mass-to-height ratio of 18 to take part.

One of the rejected models had only reached a ratio of 16, the equivalent of being 1.8 meters (5 feet 10 inches) tall and weighing less than 50 kilograms (110 pounds), said Dr. Susana Monereo, of Madrid Getafe hospital's endocrinology and nutrition department, who along with two other doctors was in charge of assessing the models.

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Monereo said this represented "extreme thinness."

Three of the five models turned away were not Spanish, Monereo said.

The five models had come from working at a New York fashion show and two of them had taken part in 25 shows before flying to Madrid for the assessment, said Leonor Perez Pita, director of Pasarela Cibeles.

"It could be that they lost weight during that period," Perez Pita said.

She said the Madrid show's aim was to convey a message of "health and beauty."

"Five hundred people will see them here, but through television it'll make it six million, and a young girl may think it's a definition of beauty and may even make herself ill as a result."

Model Raquel Brel, who at 1.82 meters (5 feet 11.5 inches) tall and 61 kilograms (nearly 135 pounds), passed the assessment, said she agreed with the terms imposed by the show.

"Excessively thin models aren't good for society and don't correspond with reality," said Brel, adding she knew of models who only ate an apple a day while working.

"There are more models who eat little than those whose weight is naturally low," Brel said.