"That has been one of my joyous moments, being able to help advocate children's rights," actress Priyanka Chopra tells PEOPLE of volunteering with UNICEF

Credit: UNICEF

Priyanka Chopra grew up in a service-minded household thanks to her two parents who served as doctors in the India army.

But it took winning Miss World in 2000 to show Chopra, 36, she could make a difference on a global scale.

“I realized I had a position of power, and I could associate myself with causes I really believed in,” the India native tells PEOPLE in this week’s issue.

For 12 years the Quantico star has worked with UNICEF as a global Goodwill Ambassador, visiting places in need like Zimbabwe and India’s Mumbai slums.

“The field trips are the most special, because you meet incredible kids and survivors,” Chopra says. “That has been one of my joyous moments, being able to help advocate children’s rights and children’s welfare around the world. That moved me so much in being able to go to places where these kids have no voice or no one listening to them, and actually shedding light on that.”

Chopra recalls meeting a young girl on one of her visits who spread knowledge about sexual health thanks to UNICEF.

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Volunteering with UNICEF has made Chopra see the world differently.

“I remember going on this first trip and there was this young girl, 13 or 14, and she was in school and because of working with UNICEF, she had learned about sexually transmitted diseases,” Chopra says. “She used to go around these slums and knock on doors herself with a bag full of condoms and talk to young girls about why they should be in school and not be married off. She got her school friends with her and they did this entire campaign after school where if they heard about a young girl being married off without her consent, she and her friends would go say it’s illegal and call the cops.”

​And she just sat with me and she was so brave. She did not care what anybody told her. She had the support of her parents.

“It makes you feel so small as a person,” she says of witnessing various conditions around the world. “And it makes you feel like the life we lived are so self-centered. We take so much for granted. It really is a way of coming back into reality and seeing the world for what it is.”

For full coverage of PEOPLE’s 25 Women Changing the World, pick up this week’s issue, on newsstands Friday.

As a result, the Baywatch actress feels more grateful for her own blessings.

“The one thing that has changed in me is, I do not take my my privileges for granted,” Chopra says. “I do not take the fact that I live in a comfortable home, I have the ability to get an education, I have a job that I want to have, I’m living the life that I choose to live.”