Brooke Shields Was 'Shocked' to See How Women Over 40 Are Treated: 'You're Put Out to Pasture'

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Brooke Shields has come a long way, and there's definitely nothing stopping her now!

In a short Instagram reel teasing the model's upcoming interview with Gayle King for Oprah Daily, Shields, 57, opened up about aging, being a career woman and the inspiration behind her empowering online platform Beginning is Now.

"I'm still in a career, I'm still working, I'm here and I was shocked by how unrepresented I was," Shields told King in the clip. She later joked, "You're either [in your] 20s and sexy and fabulous or you're in Depends and you've got dentures."

While Shields believes that "from 40 on we start living in our lives," she expressed that the culture doesn't reflect that reality.

"We're not marketed to!" she said. "Once you're over, you stop working; you're, like, put out to pasture. I was incensed by that."

"When I think about beginnings, I feel like it's now," she said of why she launched her women-driven, community-centered brand. "I wanted women to be able to feel that."

"We're not asking for permission," she declared while adding that she wants to encourage women of all ages "to try new things, to say look how long I've lived and look how much more I have."

Shields and King's interview will go live on July 28 at 8:00 p.m. EDT.

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Beginning is Now is just another way the Blue Lagoon continues to spread her positive mantra around aging and acceptance.

"It's exhausting entertaining your insecurities," she told PEOPLE in February while partnering with denim brand Jordache for its Spring 2022 campaign. "It is truly exhausting ... I'm not criticizing myself for all the things that I'm not, which I did a lot of in my younger years. I did a lot of comparison, and that's just a losing game."

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RELATED: Brooke Shields Says She Was Mom's 'World,' Wants Her Girls to Know She's 'Not Their Responsibility'

Shields also believes that, in doing this, she sets a good example for her two daughters Rowan, 19, and Grier, 16, whom she shares with husband Chris Henchy.

"I realized that I can't represent [comparison] to my daughters. So I tried to turn it all around a little bit, in how I chose to see myself," she told PEOPLE, adding that "it's not an easy task, and you have to really remind yourself and keep practicing it."

Brooke Shields/Instagram

RELATED: How Brooke Shields Found Body (and Bikini) Confidence at 55: 'Women Over 50 Are Not Done'

Even in her fashion sense, Shields has come to learn that embracing her body is a powerful style statement on its own, especially when it comes to her confident bikini selfies.

"I was wearing those big bathing suits that had as much fabric as possible," she tells PEOPLE. "My daughters were like, 'Mom, it's ridiculous.' It was sort of seeing myself through their eyes and just celebrating things like my butt. Things I just would never want to focus on in my life. Being 55 and saying 'Wait a minute, women over 50 are not done.'"

RELATED: Brooke Shields Credits Her Daughters for Style Inspiration: 'They Understand Fashion Differently'

In May, Rowan also spoke to PEOPLE on this very lesson while attending the opening of Fashionphile's latest New York City Authentication Center & Showroom alongside her mom and Grier.

"We're a big boned family [and] we've got some hips. And so if there's one thing she's said it's just, 'Wear things that are tight, why not?'," Rowan shared. "It's flattering and not to be provocative or scandalous or anything, but just to show off what you have."