Naumoska insisted to "GMA" that she is not malnourished.
"If I was [malnourished], my skin would be suffering, and my hair. I wouldn't have the energy to enter modeling contests," she said.
Naumoska, who some experts said should weigh 135 pounds, is just the latest in a long line of young women whose lean bodies have sparked debate.
Pictures of a skeletal Lindsey Lohan have some wondering if a shrinking waistline is the 22-year-old star's way of crying out for help.
Nicole Richie, Katie Holmes, Victoria Beckham, Angelina Jolie and Kate Bosworth are just a few of the A-list celebrities whose willowy frames have garnered inquiries.
It's this criticism that Naumoska spoke out against.
"I want to defend all the skinny girls out there, all the celebrities and people who get criticized about their appearance," she said. "Some people are naturally skinny."
But experts say there is a line between naturally skinny and unhealthily skinny.
21-year-old Brazilian model Ana Carolina Reston brought weighty issues to the forefront of the news in 2006 when she died of causes linked to anorexia. Another model Luisel Ramos died during Uruguay's fashion gala after weeks starving herself before the show in 2006.
For her part, Naumoska insists she is healthy.
But that couldn't win her the crown. That honor went to Rachel Finch, who will go on to represent Australia in Miss Universe world finals in the Bahamas in August.
Reuters contributed to this story.