But on Friday, the 30-year-old shared a flashback photo on Instagram proving otherwise.
Reassuringly, just like most of us, the model had an awkward teen phase which even included a spiked gel hairstyle.
He casually captioned the photo, “Big boy at prom with @krystleambers... #ThrowbackThursday.”
The Australia’s Next Top Model mentor candidly spoke to TheFix about growing up overweight.
“You'll freak out,” Didier admitted to the entertainment site about his portly teenage years.
He candidly added: “I was really overweight, and I was just embarrassed sometimes to take off my shirt at the beach.”
The now-model decided to make a change when he was 19-years-old.
"I started running, doing a little bit of cardio, looking at what I was eating, not being super strict but just knowing what was healthier."
These days, the Australia's Next Top Model star credits his happiness and clarity to his clean lifestyle and working out “like a ninja”.
He explained: "For me, it's all about the mental aspect.”
"After I exercise, my head is clear, my mind is clear, everything is clear. I'm more happy. It shows me that things I thought were impossible aren't."
Despite making a complete change, Didier uncovered that modelling would scrutinize the way he looked, in ways that would become a testament to his character and inner strength.
It all changed when the American-born personality got his big break at the age of 22, where he modelled with Miranda Kerr for Australian menswear brand Industrie.
"People said I was too tattooed, I wasn't the right type of look," he said. "And then the Industrie campaign with Miranda Kerr changed my whole career. Everything took off from there."
Didier has since transitioned off the runway and into our homes as the modelling mentor on the fashion show, Australia’s Next Top Model, and now he hopes to make another segue - this time to the music industry.
The model is a self-proclaimed music lover who loves DJing and has since signed deal with a major record label! His first single, Skyline, will be released in August.
"There is nothing in the world like creating the song, writing the song, putting your all into it, going in front of thousands of people and playing that song and seeing everyone have a positive reaction to it. It's just a trip. It's my drug of choice," he added to The Fix.