More people than you may have thought are on plant-based and animal-free diets: PETA reports that 2.5 percent of U.S. residents are vegans, while another 5 percent are vegetarians. Celebrities are no strangers to these dietary changes; big names like Bill Clinton, Ellen DeGeneres and now Al Gore are all on board with veganism.
Just how nutritious is this plant-based diet, though? Experts note it can be one of the healthiest ways to eat, as you’ll limit calories and harmful fats while still consuming vitamins and minerals. It’s also good for the environment; it uses fewer resources, and doesn’t support industrial livestock farms, which often face criticism for their treatment of animals and environmental waste.
Many celebrities have adopted the diet for personal, health, or environmental reasons, and are speaking up for this lifestyle. Take a look at some of veganism’s most prominent supporters below.

"I like the vegetables, the fruits, the beans, the stuff I eat now," Clinton told a CNN reporter. "All my blood tests are good, and my vital signs are good, and I feel good, and I also have, believe it or not, more energy."
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It's not a completely strict meatless and dairy-free diet for this country star, though: She'll slip up for cultural or social reasons if need be. "I am a vegan but I consider myself to be a practical vegan," she told Entertainment Wise. "If I order something on a menu and it has a sprinkling of cheese on top I'm not going to send it back."
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The actress reverted to vegetarianism during her 2011 pregnancy, US Weekly reports, citing that her body was craving foods made with eggs and cheese. Post-pregnancy, Portman readopted the animal-free lifestyle. Her 2012 wedding was actually catered with an all-vegan menu.
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Perhaps one of the more vocal celebrities on this diet, she even has her own vegan blog, "Going Vegan With Ellen," and she and de Rossi are slated to open their own vegan restaurant, though its opening date is unknown.
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The New York Times reports that this lifelong animal lover made the switch after watching documentaries on the food industry. Silverstone authored The Kind Diet, a book on vegan cuisine in 2009, and offers other diet pointers and green tips on her website, The Kind Life.
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Usher apparently tried to get his protégé, Justin Bieber, aboard the vegan train too, but he hasn't stuck with it.
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This past February, he simulated the concept of a drowning fish in a controversial video for PETA's "Go Vegan" campaign. PETA wanted to run the ad as a commercial during the Academy Awards, but ABC refused to air it, reports Business Insider.
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In the introduction to Very Vegetarian by Jannequin Bennett, Lewis explains that he went vegan after meeting two people, a doctor and a nutritionist, that inspired him to switch his diet. Though he acknowledges there were hurdles to cross, such as cravings for meat and salt, he found other substances like lemon juice and lentils to make his diet enjoyable.
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Harrelson isn't just a vegan, but also environmentally conscious. He resides on on a working organic farm in Maui with his family, refuses to talk on a cellphone because of electromagnetic waves, and prefers to drive energy efficient cars, the Esquire article explains. According to Mother Nature Network, he's a co-owner of Sage, a vegan restaurant and the world's first organic beer garden that opened this past fall.
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CORRECTION: A previous version of this article misstated the name of The Smiths' song "Meat is Murder." This article also previously included Betty White, who is an animal lover but not a vegan.