Alissandra Moone, who weighs 57kg, said that she was "stunned" when fashion designer Alex Perry likened her to "overstuffed luggage" and has accused the reality series of sending out a poor "message" to fans.
Moone told The Daily Telegraph: "It's a very bad message to be sending to young girls who watch the show. It's harsh. It's stupid. And it's out of touch. I understand it's a reality of the industry but this is a TV show and they should have a responsibility to censor that kind of thing.
"I know this has happened to other girls in the past but I was shocked when he said I was too fat. I'm only a size eight. There's going to be a lot of young girls watching this who are bigger than me, and how's this going to make them feel?
"I understand it's probably a reality of the industry but no one likes to be told they look fat - regardless of what job you are in. I have never thought of myself as fat. I am a health freak. I go to the gym and eat well."
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A spokesperson for eating disorder charity the ButterFly Foundation has now weighed into the debate, saying: "The industry has a responsibility for portraying women of all healthy sizes and in playing a strong educated role in the contribution they make to the serious issue of negative body image. We encourage Top Model to be conscious of the example they set to their impressionable viewers."
Former Australia's Next Top Model contestant Sophie van den Akker is the face of Melbourne Spring Fashion Week this year and is also a size eight. She said: "As a role model, I think an eight to ten is more realistic. I think people are more attracted to that than seeing skin and bone."
Aussie TV star Ajay Rochester recently accused Perry of "hating fat women". Perry later called her claims "reprehensible".
Watch a showreel of Alissandra and the top 20 Australia's Next Top Model contestants below: