Some of Hollywood's elite refuse to eat meat. See why these famous folks made the switch:

The animal rights activist and actress began a vegetarian lifestyle when she was still a kid. Eventually, she became a devout vegan. Portman feels so strongly about the equal treatment of animals that she started a vegan shoe line in 2009. When pregnant with her first child, however, Portman switched to a vegetarian diet because she says her body was craving eggs and dairy.

The former president used to be known for his love of McDonalds, and junk food in general, but after two separate heart procedures, Clinton shied away from the bad stuff. Clinton changed to a vegan diet when he realized a major food overhaul was necessary for his health to truly improve. The former president now says he no longer consumes meat, dairy or eggs, and consumes very little oil.

Even though Mike Tyson looks fierce, he’s got a soft spot for animals. Originally going vegan to follow his diet-trendy wife, Tyson's way of life ending up sticking long after his wife’s fad faded. “I wish I was born this way. When you find out about the processed stuff you have been eating. I wonder why I was crazy all those years,” he said in a Fox News interview.

Alicia Silverstone

One of the first to speak out about eating less meat, Alicia Silverstone, author of The Kind Diet, even keeps her baby on a vegan diet. “Nothing’s changed my life more,” the actress said. “I feel better about myself as a person, being conscious and responsible for my actions,  plus I lost weight and my skin cleared up and I got bright eyes and I just became stronger and healthier and happier. Can’t think of anything better in the world to be but be vegan.”

Carrie Underwood

One of PETA’s Sexiest Vegetarian Celebs, Carrie Underwood upgraded her commitment to eating animal-free when she announced her switch to veganism. The “kind of lactose-intolerant” star made the transition this past June.

Pam Anderson

Another PETA heavy-hitter, Pamela Anderson often speaks about how a vegan diet helps her keep healthy. At a PETA event in 2010, Anderson said of her diet, “I always feel healthy, but I feel better.”

Russell Brand and Kristen Wiig

PETA named the comedy duo this year’s sexiest vegetarians. A vegetarian since he was 14, Brand told PETA, "You shouldn't eat animals, it's mean to them." Being a vegetarian helps Wiig maintain her svelte figure by “eating lot of tofu and soy,” she told Women’s Health.

Vegetarian for more than 14 years, Toby Magurie stepped things up a notch when he decided to ban all leather from his house. That’s right --  those visiting the actor must remove all shoes and belts made of animals before entering his home, according to ecorazzi.com. Today, he eats completely vegan unless he’s trying to bulk up for a role, in which case he adds small amounts of eggs and dairy.

The actress may be best known for making waves as a mermaid in Splash, but she’s making waves in other ways these days. Living in a solar-powered home in the Rockies, Hannah is a champion for animal rights and has been since age 11. Now, she is a strict vegan.

Vegan since 2008, Ellen DeGeneres is all about promoting a vegan lifestyle. She recently started her “Going Vegan With Ellen” website where she offers tips, tricks and advice for the first-time vegan.

More Celeb Vegetarians: Kristen Bell, Milo Ventimiglia, Jane Goodall, Olivia Wilde (previously vegan), Paul McCartney and Alyssa Milano.