EXCLUSIVE: Ariel Winter Slams Donald Trump for Body Shaming Women: 'It's Really Disappointing'

The 18-year-old actress tells ET she has her own plan on how to 'empower' young girls.

Ariel Winter certainly won't be voting for Republican presidential candidate Donald Trump in the upcoming election.

ET caught up with the Modern Family star at the London Hotel in New York City on Thursday, where she slammed the 70-year-old businessman for the lewd comments he made about women while speaking with then-Access Hollywood host Billy Bush in a leaked video from 2005.

WATCH: Ariel Winter Bares Her Booty in Signature Daisy Dukes -- See the Cheeky Pic!

"I think it's really disappointing that we've made so many strides towards promoting body positivity for women -- and for men -- and for empowering women, and he really kind of just tears it all down," the 18-year-old actress dished. "I think it's really disappointing that he's made it this far -- that he is a presidential candidate, and this is possibly the person who will be representing the United States."

Winter, who has been named the new Dove Self-Esteem Project #SpeakBeautiful squad leader, also opened up about her own past struggles with self-esteem.

"For many years, I faced tons of online criticism from cyber bullying," she admitted. "I had a ton of self-esteem issues, so I had a really long body positivity journey of learning to be confident in myself."

The Los Angeles native told ET becoming comfortable in her own skin has "definitely been a long journey," but she's finally learned to block out the haters.

WATCH: Ariel Winter Works Out With the Kardashians' Personal Trainer

"When I was first in the spotlight, I was flat-chested and I had no curves and was getting hate for that," she confessed. "Then, I turned 12 and automatically had boobs and a butt and a curvy body and it was something, at first, that I was really excited about, until photos started coming out of me on the Internet and people started really, really hating on what I looked like."

"I was called fat and ugly and a slut, and a lot of things for just being me, and it was really difficult," she continued. "For many years, I did my best to try and [crash] diet to lose weight, or change the way I dressed, and change the things I talked about to see if it would help and to see if people would reply more positively to me if I did that."

"I finally said to myself, 'You know, I'm wasting so much time trying to please other people when I should really should be focusing on the most important relationship I have, which is the one I have with myself.' And I took that time to really focus on me, and to understand that people's comments aren't what matter."

Now, in her collaboration with Dove, Winter says she hopes to "empower young women and young men to not only feel confident in the way that they look, but to feel confident in who they are as a whole."

WATCH: Ariel Winter Says She's 'Jaded' When It Comes to Criticism, Calls Online Judgment 'Sexist'

"I think that is a really important message," she explained. "To make them feel like their opinions are heard, that they are unique and beautiful and smart."

"That also translates to another thing that we are working [on], which is speaking beautifully on the Internet," she added. "Unfortunately, we're in a day and age where speaking positively [online] is not something that happens often. There's a huge cloud of negativity that's kind of raining down on everyone’s social medias platforms, so what we're trying to do is to teach young women and young men how to be positive."

The brunette beauty also admitted that although she's much more confident today, she still has her bad days. "I definitely still get insecure occasionally, I think everybody does," she said. "No matter how confident you are, occasionally there will times where those thoughts creep back in your brain. Everybody's going to have those thoughts, but it's just about how you deflect them and change the conversation in your own mind that really matters."

Back in August, Winter told ET that she was beyond excited to be voting in her first election, but wishes "we had better candidates" than Trump and Hillary Clinton.

WATCH: Ariel Winter on Getting Ready for College and Voting in Her First Election

"I absolutely hate Donald Trump. Just, to be honest," she exclaimed. "I'm pretty disappointed that these are the candidates now. We've come so far, yet the candidates don't really reflect the amazing strides we've made."

To hear more on her political stance, watch the video below.

- Additional reporting by Darla Murray