The TOWIE star, who came in third place in I'm A Celebrity...Get Me Out Of Here!, was subject to negative comments from online trolls while she was in the jungle.
Posts shared on social media compared photos of Ferne in the jungle with some of her recent campaign lingerie shots.
At the time, Ferne's mother Gill hit out at the "vile" bodyshamers, and now, Ferne has told The Mirror: "In a campaign, that picture is the brand's baby. They want it to look perfect, just like if you're painting a picture. All pictures get retouched. I'm aware of that and I thought everyone else was as well."
Ferne, who lost 7lbs in the jungle, continued: "I always promote being natural and embracing what you've got. Don't get down about comparing yourself to models on social media.
"I want girls to realise that Instagram isn't real. Maybe I need to do a campaign. It gets me down, girls looking so perfect."
Ferne also said that use of some photo editing apps can be a bad thing: "It's a personal thing. I might want to smooth a bit of my skin. But it becomes obsessive. It's worrying. But I've been in the jungle wearing no make-up, so people can see what I look like."
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