"Can you lift up your top?" I'm A Celebrity's Simone Holtznagel on weight pressures.

Australian model Simone Holtznagel said she was 19 when she was told lose weight by a modelling agent who recommended she “just drink one can of Coca-Cola and have an apple a day”.

Appearing on I’m A Celebrity, Get Me Out Of Here!, the 24-year-old former Guess model told fellow contestants Fiona O’Loughlin and Josh Gibson about the harrowing ordeal which happened at an agency in Milan.

“I went in the room and [the agent] said ‘Can you lift up your top?’,” Holtznagel said.

The female agent told her: "You look good but you have a lot of baby fat around your face. Maybe you should lose some weight." This was followed by the coke and apple recommendation.

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Holtznagel said she saw the same woman years later in Los Angeles, where she was again told: "Well you look great now, but I think maybe you should lose some more weight."

By that time, Holtznagel had modelled for Guess.

"There's a lot of pressure as a model to look a certain way all the time, which is difficult," Holtznagel told the camera on Sunday night's program.

She said she eventually stood up to the woman, telling her: "Well I just did my first campaign for Guess and everyone f**king loves me."

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Holtznagel, originally from Wollongong in NSW, shot to fame in 2011 when she was awarded second runner-up in Australia's Next Top Model.

While on the show, the then 17-year-old was mentored by the late Charlotte Dawson, who Holznagel describes as "one of her best friends".

On Sunday night's I'm A Celebrity, Get Me Out Of Here! psychic Jackie Gillies told Holtznagel that Dawson was "sorry" for the way she left. Dawson was found dead in 2014 by suicide, aged 47.

"She is telling me you have a lot of anger as to why she did what she did," Gillies told Holtznagel.

"And she’s telling me to tell you she had financial distress. She is telling me it all got too much for her. She is sorry with the way she left."

"She is telling me to tell you not to cry, she knows how much you miss her. She says you are her little sister, that is how she views you."

After the reading, Holtznagel said she felt "so much lighter" as if she was "floating".

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