It's hard to imagine someone calling Christie Brinkley and Ashley Graham anything less than absolutely stunning. But as it turns out both models faced a lot of scrutiny for their famous curves early on in their careers.

In this exclusive clip (above), the duo, who star in NYDJ's "Fit to Be" campaign, sit down with host Amanda de Cadenet for a candid chat about body image and finding their footing in the fashion industry. "There are a lot of barriers that society places on us and it's up to us to just keep talking and speaking out," Brinkley says. "I was actually considered too curvy. ... I went into the modeling agency and they said, 'Yes, we want you,' but the first thing I thought was, 'How do I lose weight to look like everybody else?' I was athletic and strong and by no means fat, but because I wasn't skinny like the other girls, I remember standing there looking that thin and thinking I was fat," she recalls.

Graham, who has broken boundaries as a body image activist and InStyle's own "Great Style Has No Size" columnist, looked to her family for confidence when she was going on casting calls. "I didn't have anybody in the media to look up to, so it was always my mom," she says. "It was a constant in my house that she was saying affirmations to herself. And it's the kind of mother I want to be. I never want to look in the mirror in front of my daughter or my son and say 'I'm fat' or say 'I need to go on a diet.' Supermodels have rolls!"

And it's that positivity that still inspires Graham today. "We're always told that we're not good enough," she says. "But the thing that I never changed was that I stayed true to myself." To see the entire clip, click on the above video. For more from Graham, check out her "Great Style Has No Size" column in InStyle's October issue, available on newsstands and for digital download now.