Beneath the glitz and glamour, these Hollywood hotties -- including Bradley Cooper, who wore a tuxedo made from recycled materials to the 2013 Golden Globes -- are tree-huggers at heart.

Bradley Cooper showed his concern for the environment by wearing a tuxedo made from recycled materials to the 2013 Golden Globe Awards in January. The suit was made from "low environmental impact" materials, according to Livia Firth, who launched the Green Carpet Challenge encouraging designers to create environmentally friendly looks for special events.

Jason Merritt / Getty Images North America

Beneath the glitz and glamour, these Hollywood hotties are tree-huggers at heart.

British pop star Paul McCartney, a longtime environmental campaigner, has urged people to fight global warming by going vegetarian at least once a week and has campaigned in Brussels for a "Meat-free Monday."

Georges Gobet / AFP

The DVD release date for director and environmentalist James Cameron's film "Avatar" was carefully planned to coincide with Earth Day 2010, and inspired several "Home Tree" Earth Day events.

Kris Connor / Getty Images North America

Musician Carole King has testified three times on behalf of the Northern Rockies Ecosystem Protection Act, and has been working with the Alliance for the Wild Rockies since 1990.

Theo Wargo / Getty Images North America

Actor and comedian Chevy Chase, a self-proclaimed "Greeny," cares about the environment in a big way. He and his wife, Jayni Chase, are the powerhouses behind GREEN Community Schools, an initiative to make schools more environmentally friendly, safe and healthy places for children to be. In support of GREEN Community Schools, Chase and actor Bill Murray have auctioned off "Caddyshack" Golf Outings to winning bidders who get to hit the links with the stars of the classic film.

Barry Brecheisen / Getty Images North America

Talk about walking the walk. "Lord of the Rings" star Dominic Monaghan actually bought a forest in India in 2003 in order to preserve it. He's a spokesman for Project Last Stand, a group that spotlights and supports people and organizations working to end the destruction of the world's forests.

Jeff Vespa / WireImage

Actress Rachel McAdams thinks being green is sexy – so much so that she and her friends started the Web site to share tips and insights about how to have a positive effect on the environment in day-to-day-life. The site describes itself as being "about tiny changes, big impact. Why sexy? Because being informed is sexy. Being responsible is sexy. Being eco-friendly is sexy. Making a difference is sexy."

Francois Guillot / AFP

Actress Maggie Gyllenhaal supports a variety of charities and causes that benefit the environment. In her daily life, she puts those sentiments into practice by using eco-friendly items at home, such as bamboo sheets, and wearing fashions made from bamboo and organic materials.

Michael Loccisano / Getty Images North America

Former supermodel Cindy Crawford described her 'eco-awakening' in 2008 on, explaining that it hit her after she had kids. "My kids were making me feel guilty!" she wrote. "They go to a very environmentally aware school, where they do beach clean-ups and hand out cloth bags and reusable bottles." Crawford went on to promote causes in support of safe, clean drinking water.

Kevin Winter / Getty Images North America

Leonardo DiCaprio has produced and narrated an environmental documentary film, "The 11th Hour" (he is shown here at the premiere of the film). The actor often flies commercially, drives a Toyota Prius and is purchasing a "green" apartment in NYC’s Battery Park City. In 1998 he started the Leonardo Dicaprio Foundation, which aims to spreads awareness of environmental issues. He also launched a website, ( that is dedicated to environmental issues and campaigns, such as the movement to stop the use of plastic bags. The actor has also lobbied for universal access to clean water and the reduction of fossil fuel emissions.

Evan Agostini / Getty Images North America

"Hereos" actress Hayden Panettiere has been an active spokesperson against dolphin hunting. Here, she speaks at a 2008 press conference for ''Save The Whales Again' Washington, D.C.

Nancy Ostertag / Getty Images North America

Actress Salma Hayek is a Global Green USA board member, and works to fight global warming and to bring clean drinking water to people in need of it. She's also a global spokesperson for the "One Pack = One Vaccine" campaign; here she visits moms and babies during a trip to Sierra Leone with UNICEF.


Carbon offsetting is one of actor Jake Gyllenhaal's main causes. The "Rendition" star journeyed with Salma Hayek to the North Pole to document the challenges facing the Inuits as their region warms up, and also donated $10,000 for trees to be planted in Mozambique.

Paul Drinkwater / NBC

Coldplay frontman Chris Martin is a celebrity advocate of fair trade. To help spread awareness of this cause, the words "Make Trade Fair" are written on the side of his piano for live performances.

Vivek Prakash / X90042

Actor Orlando Bloom helped launch Global Cool, an organization that aims to bring small, simple changes into people's routines to combat global warming. He also traveled to Antarctica with Global Green USA to study the effects of warming on the region.

Kevin Winter / Getty Images North America

Actress and longtime vegetarian Cloris Leachman donned a gown made of lettuce and cabbage leaves for a PETA campaign called "Let Vegetarianism Grow on You." Here, she unveils the 2009 ad in New York's Times Square.

Neilson Barnard / Getty Images North America

British fashion designer and vegetarian Stella McCartney runs a wind-powered studio and Web site. Online buyers have the option of having their organic garments shipped in a carbon neutral way. Here, McCartney attends the Natural Resources Defense Council's 11th annual "Forces For Nature" benefit in New York City.

Andrew H. Walker / Getty Images North America

Australian Cate Blanchett is not only an actress, but also the artistic co-director of the Sydney Theater Company. She aims to get the theater off the grid for a whole season by installing solar panels and reusing rainwater, as she does in her own home.

Mario Anzuoni / X90045

Singer Sting and his wife, Trudie Styler, created The Rainforest Foundation in 1989, and have already protected more than 71,000 square miles of land in Brazil, Latin America, Africa and Southeast Asia.

Stephen Lovekin / Getty Images North America

Former model Heather Mills is known for her activism for vegetarianism and animal rights. She's also a PETA spokesperson, speaking out against dog fur trade, and has also campaigned against the use of landmines. Here she attends Viva! The Incredible Veggie Show at the Royal Horticultural Halls in London.

Chris Jackson / Getty Images Europe

Musician Sheryl Crow lends her environmental support for clean diesel and poses here with a Mercedes-Benz ML320 BlueTEC SUV. Crow says, "the newest clean diesel vehicles are eco-friendly and deserve as much attention as other gas alternatives like hybrids." She also threw an all-natural baby shower for her newborn son, Wyatt.

Albert Michael / MERCEDES-BENZ USA

British television cook Jamie Oliver is a proponent of the local food movement, a theme that's central to his TV series "Jamie at Home." He's also made over the lunch programs at 60 British schools, and his Cornwall restaurant, Fifteen, will run on wind power.

Federico Gambarini / dpa

Adrian Grenier, a star on HBO's Entourage, resides in a green home which he rebuilt along with his mother. The Brooklyn house is insulated with recycled blue-jeans, has a solar roof and reclaimed oak floors. When in L.A,. the actor drives a Prius. He is currently filming a 13-part series called "Green Life" for the Discovery Channel's new environmental venture, Planet Green. The show will highlight small steps people can take to make their lives greener.

Chris Pizzello / A-PIZZELLO

Long before she played Elaine on Seinfeld, Julia Louis-Dreyfus and her husband Brad Hall were devout environmentalists. Dreyfus has also long been active with organizations like Heal the Bay, the Natural Resources Defense Council and the Trust for Public Land. The couple also live in an eco-friendly, oceanfront home that is complete with solar panels and a retractable roof for natural cooling and heating.

Frederick M. Brown / Getty Images North America

Yes, even the captain of the Virgin empire is seeking to offset his prodigious carbon footprint. For example, Branson's Virgin Green Fund invests in companies in the renewable energy sectors (wind, solar, and water power) in the U.S. and Europe. Here, Branson poses in February 2008 in front of a Virgin Atlantic Boeing 747 before it embarks on the first test flight using bio-fuel made from coconut oil. In March 2008, Branson hosted an environmental conference at his "green" private island, Necker Island. Attendees included British Prime Minister Tony Blair, Google's Larry Page and Wikipedia founder Jimmy Wales.

Ben Stansall / AFP

Woody Harrelson and Owen Wilson pose for photographers during a visit to the Andean city of Cuzco, Peru, in December 2007. The actors reportedly were visiting a nearby orphanage they support. Wilson, who drives a Prius, also uses solar panels to power his home. He also contributed a personal essay to "The Green Book," a 2007 guide to living green. Meanwhile, vegan and raw foodist Harrelson is an environmental, peace and animal rights activist. The 2003 documentary film "Go Further" followed the actor on a bio-fueled bus trip and mission to raise awareness about environmentally-destructive behaviors.

Str / AP

Actor and Hollywood environmental leader Ed Begley Jr., drives an electric car, owns a solar-powered home and has his own brand of eco-cleaners called Begley’s Best. He serves on the boards of the Environmental Media Association, the Santa Monica Mountains Conservancy and the Thoreau Institute, among many others. He and his wife Rachelle Carson currently star on the HDTV program "Living with Ed," a reality show which puts a domestic spin on green issues.

Matthew Simmons / Getty Images North America

Actor/director Robert Redford regularly speaks out for clean, sustainable and alternative energy production, and also for clean air and water. Since he was a young man, Redford has campaigned to preserve the Utah wilderness through various trusts and alliances. Redford also recently launched a weekly three-hour slot of eco-programming called “The Green” on his Sundance TV channel.

Chip Somodevilla / Getty Images North America

Actor Pierce Brosnan's activism is focused on wetland and marine mammal protection. He also serves on the board of the Environmental Media Association, and has been aligned with the National Resources Defense Council and International Fund for Animal Welfare. He was named "best dressed environmentalist" in 2004 by the Sustainable Style Foundation.

Vince Bucci / Getty Images North America

Longtime environmentalist Daryl Hannah has a weekly video blog called DH Love Life, which is devoted to highlighting sustainable solutions, plus she drives a car that runs on biodiesel. Her two houses have been off the grid for years, running on solar panels and graywater systems. She also buys carbon offsets for all her travel. Here, Hannah and her nephews present an award during the 2005 Environmental Media Awards in Los Angeles.

Stephen Shugerman / Getty Images North America

Actor and advocate of sustainable energy George Clooney drives an electric Tango car, and has reportedly ordered a $100,000 electric Telsa Roadster. He also launched Oil Change, a campaign to reduce America’s dependence on oil. His eco-efforts landed him the cover of Vanity Fair’s 2006 green issue alongside Julia Roberts, Al Gore and Robert F. Kennedy Jr. His non-environmental do-good efforts include being a strong supporter of the organization Save Darfur.

Gareth Cattermole / Getty Images Europe

Braided Texas singer Willie Nelson has his own line of biodiesel fuel, BioWillie, which is made from vegetable oil (mainly soybeans). The fuel can be burned without modification to diesel engines, and his company, Willie Nelson’s Biodiesel, is marketing the fuel to truck stops. Nelson is also the president of Farm Aid, an organization whose mission is to keep family farmers on their land. Here, he performs in 2004 at the "Earth To L.A.: The Greatest Show On Earth" event, which raised more than $2 million for the Natural Resources Defense Council.

Vince Bucci / Getty Images North America

Ted Danson was a founder of Oceana (formerly the American Oceans Campaign) and has donated more than $500,000 to environmental causes. He is shown here (with the soft toy fish “Finley”) in November 2007, after he brought forth a bid to the World Trade Organization that would protect the world’s oceans and marine life from over-fishing.

Fabrice Coffrini / AFP

Golden Globe-winning actor Edward Norton created the BP Solar Neighbors Program, which aims to help lower energy costs for struggling Los Angeles families through the use of solar power. He has also campaigned with Friends of the Highline, an organization which works to save and re-build green space in Norton’s hometown of New York City. He hosts a four-part PBS National Geographic series called “Strange Days on Planet Earth,” which explores the environmental challenges facing our planet.

Matthew Simmons / Getty Images North America

Actress Natalie Portman has been a vegetarian since childhood and is also an advocate for animal rights and environmental causes. She also has her own line of vegan, cruelty-free footwear for specialty retailer Té Casan. All proceeds from the line will benefit the Nature Conservancy, an organization that is dedicated to ecological preservation.

Sean Gallup / Getty Images Europe

Tom Hanks supports The Nature Conservancy through radio and TV PSAs and drives an electric car. He recently starred in the 2006 documentary “Who Killed the Electric Car,” where he gave commentary on the electric car, and discussed the ongoing conflict over oil. He’s shown here at the 2004 “Earth To L.A.: The Greatest Show On Earth” event alongside actor Jack Black.

Vince Bucci / Getty Images North America

Longtime vegetarian Alicia Silverstone owns a solar powered, green home and is also an outspoken animal activist. She also promotes the use of energy-efficient light bulbs and bamboo for wood flooring. Her teen cartoon series "Braceface" was nominated for an Environmental Media Association Award for its incorporation of environmental messages in the show. (Silverstone is shown here presenting at the 2005 Annual Environmental Media Awards.)

Stephen Shugerman / Getty Images North America

Vocalist Adam Levine and his band Maroon 5 teamed up with a charity organization called Global Cool to make their 2007 world tour a green adventure. Besides driving in a biodiesel bus as often as possible, the band also used $1 from every ticket sold on the U.S. part of the tour to offset carbon emissions. In 2006, the band won the Environmental Media Award's Futures Award for their eco-efforts. They also supported the Nuke Free campaign, which aimed to stop Congress from financing the nuclear energy industry.

Peter Kramer / KRAPE

Actress Blythe Danner here attends an April 2008 press conference for the unveiling of New York City's natural gas burning sanitation trucks. She also drives an electric car, and encourages the use of alternative energy sources through public service announcements (along with her daughter Gwyneth Paltrow). Danner is also on the board of the Board of Environmental Activists and the Board of Directors of the Environmental Media Association.

Brad Barket / Getty Images North America

Former U.S. Vice President Al Gore and the Intergovernmental Panel on Climate Change together won a Nobel Peace Prize in 2007 for their efforts in elevating awareness about man-made climate change. Here, Gore speaks during one of the eight Live Earth concerts in 2007, as actress Cameron Diaz (who helped promote the project) reacts. Gore organized the high-profile concert event to help raise awareness about global warming, something he also did with the 2006 Oscar-winning film, "An Inconvenient Truth." The Prius-driving Diaz has also aligned herself with green causes: She hosted an MTV show called "Trippin," which looked at environmental issues around the world, plus she has filmed public service announcements about the importance of conserving energy.

Justin Lane / EPA

Alicia Keys played for Al Gore’s Live Earth, a series of worldwide concerts in 2007 that aimed to raise awareness of climate change. She is also a supporter of Eco 4 The World, an organization that works to promote a sustainable future.

Joao Relvas / LUSA

Gwyneth Paltrow is sowing the seeds of a new green generation, one heap of manure at a time. The actress maintains a compost pile in her backyard, teaching her children green values early on.

Matt Sayles / AP

In addition to his other do-good efforts, actor Brad Pitt's Make it Right program will build 150 ecologically sustainable homes in the Lower 9th Ward next to one of the levee breaches in New Orleans (here, he stands before the project’s pink stand-in structures). Pitt also supports Edward Norton's Solar Neighbors program, which promotes the use of solar power, and has narrated a sustainable design TV series for PBS called "Design: e2."

Matthew Hinton / AFP