And the Oscar goes to ... Planet Earth?

From plant-based meals to repeat tuxedos and water bottle bans, Hollywood has come to embrace sustainability in an awards season usually known for excess.

Some of Hollywood's biggest stars, many of whom are vocal about environmental issues, are now turning words into action on red carpets and at gala dinners as they crisscross the United States for award shows and appearances.

Dinners at the Golden Globes, Screen Actors Guild and Critics' Choice Awards in January served up vegan fare, while the Academy of Motion Picture Arts and Sciences has banned plastic water bottles at all Oscar events and said all food served will be sustainably farmed.

"Consuming animals is no longer just a personal choice. It is having a drastic and vast consequence on the rest of the world and all of us," said "Joker" best actor Oscar nominee Joaquin Phoenix, a lifelong vegan who encouraged organizers of the Golden Globes to switch to an entirely plant-based menu for the first time.

Others are ditching planes and private jets for electric or hybrid cars as they travel to film festivals in California and beyond.

"Stranger Things" actor Brett Gelman is among those who say they have been spurred to review their lifestyles. "I plan to change a great deal in my diet and the way I use energy, composting, the way I purchase clothing. ... I'm certainly not taking any private jets," Gelman told reporters last month.

Inspired by teen activist Greta Thunberg, Jane Fonda is bringing her Fire Drill Fridays climate change protest from Washington to Los Angeles, two days before next Sunday's Oscar ceremony.

To be sure, there is still a way to go. While celebrity gift bags this season include items like a "self-watering, self-fertilizing farmstand" they also offer cruises on luxury yachts.

Guests at the MusiCares gala dinner for rock band Aerosmith last month were served steak and chicken, on the same plate, and "The Marvelous Mrs. Maisel" actress Alex Borstein quipped that she planned to head to a steak house after a vegan dinner at the Critics' Choice Awards in January.

'NO HOLLYWOOD ON A DEAD PLANET'

The youth arm of the group Extinction Rebellion plans a protest at the famous Hollywood sign on the eve of the Academy Awards, aimed at persuading the entertainment industry to do more.

"Some stars of Hollywood are aware of the scale of the climate crisis, and some have started to take action. ... But we do not believe that Hollywood as a whole has taken an acceptable stance on the climate crisis," the group said in a statement, announcing the protest.

"There is no Hollywood on a dead planet," the group added.

Daniel Hinerfeld, director of content partnerships at the Natural Resources Defense Council, said the publicity around initiatives like vegan dinners "shows the power that Hollywood has to start conversations, to set trends, and to shift attitudes."

But he urged the industry to do more and to use its storytelling powers to highlight climate change.

"We really need to see more film and TV that really is dealing with all of the incredibly complicated and dramatic and potentially comedic aspects of climate change, which is this huge drama," Hinerfeld said.

Red carpet fashion may be slow to catch up, despite the influence of designers like Jean Paul Gaultier, whose Paris retirement show in January featured upcycled haute couture, including skirts made out of silk ties.

Phoenix, who has won a slew of awards this year, won kudos in January for his plans to stick with the same tuxedo throughout the season.

"He chooses to make choices for the future of the planet. He has also chosen to wear this same tux for the entire award season to reduce waste," tweeted designer Stella McCartney, who provided the tux.

It remains to be seen whether other stars will follow suit, or choose recycled gowns for the world's biggest red carpet at the Oscars.

Rising New York-based designer Daniel Silverstein, who creates clothing from remnants and scraps, says he has not so far had any red carpet approaches for his Zero Waste Daniel label, although he is prepared to give A-listers the benefit of the doubt.

"People in Hollywood and the music industry are fanatical about using ethical beauty products. So I am sure there is a lot of sustainability under the surface that we don't even realize," he said.

"What I would hope to see more of is people with a platform using their opportunity to talk about their personal style and to change the conversation."