Hollywood's golden boy Leonardo DiCaprio also ranks as their greenest boy. From his global warming doc "11th Hour" to his green NYC condo, he acts as a leader in the eco-celeb movement. In honor of Earth Day, we look at the greenest stars in the biz.
Hayden Panettiere may act like a Hollywood diva, but she's PETA's celeb darling. An animal and environmental activist, she received the "Compassion in Action Award" for interfering with Japan's annual dolphin hunt. Save the Dolphins, save the World.
A long-time vegetarian and animal rights advocate, Natalie Portman traveled to Rwanda to help film a doc about silverback gorillas. She definitely caused a new vegan trend among nerdy boys who watch "Garden State" in their parents' basement.
When he isn't busy adopting children or looking like a stud, Brad Pitt spends his time helping the green movement. He started a green bulding project in New Orleans, which helped the green building trend. A real trendsetter, that Brad.
Sheryl Crow has been an outspoken environmentalist for years. From riding a biodiesel bus to chewing Karl Rove out for his disinterest in global warming to her joking attempt at limiting toilet paper usage, she's a force to be reckoned with.
Salma Hayek, a member of the board for Global Green USA, is an advocate for fighting global warming and providing clean water to billions. Prince could write a song about that instead of her curvy figure, but sales probably wouldn't be as high.
An active environmentalist, Adrian Grenier lives in a completeley green house and offsets. He says he's "fully committed to educating any lady who dares walk into his green life." Just doing his part to raise awareness in the supermodel community!
Another Global Green member, Penelope Cruz not only drives a hybrid, but has been integral into ridding red carpets of gas-guzzling limos. Though she'll have to find some larger hybrids because some celeb egos couldn't possible fit in a two-door.
Sienna Miller serves as an ambassador for climate-change campaign Global Cool and launched a carbon-neutral clothing line. She's been honored for using her celebrity to draw attention to the global warming crisis. She's definitely got our attention.
A Global Green ambassador, Orlando Bloom traveled to Antarctica for the cause. His GF Miranda Kerr has had issues with his shower water conservation and other greening tactics. Risking a relationship with a Victoria Secret model? That's commitment!
Who says Gwyneth Paltrow is all fame and GOOP? A long-time environmentalist, she keeps a green household and has a compost heap in her backyard. She's also selling her old designer clothes for charity. At least they're not being composted.
Cameron Diaz was an early outspoken green celeb. She filmed an MTV eco-series called "Trippin" where she traveled to Bhutan and Patagonia. She drives a Prius and carbon-offsets her travels. And we thought she was all giggles and bronzer.
Woody Harrelson goes green in style. He went on a national campaign, cruising in a hemp oil-fueled, biodiesel bus championing clean energy and organic agriculture … though some of the organics he promotes might be a bit more controversial.
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