Actress Jessica Chastain volunteers with the Humane Society of the United States and tells PEOPLE, "I've adopted every animal I've ever had"

By Dana Rose Falcone
November 02, 2017 11:46 AM

Jessica Chastain doesn’t want people to pity her three-legged rescue dog, Chaplin, when they see him out on a walk with her.

“He is so excited to be there with me going on a walk down the pavement, hopping along with the biggest joy you could ever see,” says the actress, one of PEOPLE’s 25 Women Changing the World. She joins fellow stars Gal Gadot, Pink, Uzo Aduba, Jessica Chastain and America Ferrera, as well as epidemiologist Dr. Celine Gounder, Whole Child International founder Karen Spencer and primatologist and anthropologist Jane Goodall, in this week’s issue.

The Humane Society of the United States volunteer, 40, supports the animal protection organization in its partnership with 200 U.S. school districts to bring plant-based menus into cafeterias and works with fashion brands to help them create cruelty-free products.

“The more success that I’ve been afforded in my industry, the more I’ve gotten to learn about what’s going on in the fashion world,” Chastain says. “I very strongly believe in buying products that are cruelty-free.”

RELATED VIDEO: Pink, Demi Lovato, Gal Gadot & More Share The Odds They Overcame To Achieve Success

Chastain, who has “adopted every animal I’ve ever had,” also favors a vegan lifestyle. “I don’t think everyone needs to be vegan,” says the Oscar nominee. “It just means helping create healthier choices for society and for our hearts at the end of the day.”

Credit: Amanda Marsalis

She does, however, want people to speak up on social media. “If there’s something that’s important to you, you can write about it and you can do so on your own platform,” she says. “You don’t have to be an actress or a journalist or run your own newspaper or have your own network to actually have a platform.”

  • Reporting by MARY GREEN