Why Lea Michele and Natalie Portman Went Vegan

Looks like scoring a table at a Hollywood steakhouse might be a little easier these days.

The newest diet trend to take on Hollywood bans red meat. And chicken. And every other food with an animal origin -- all in the name of clean eating and promises of a healthier body.

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But does this eating regimen really ring true? Or are celebrity followers like Lea Michele, Natalie Portman and Kellie Pickler at risk for a health scare?

Eating vegan basically means consuming only plant-based foods like vegetables, fruits, beans, and whole grains. Since these foods are so low in calories, "counting calories is simply not necessary!" says celebrity nutritionist Cynthia Pasquella.

In fact, studies have shown that followers of a plant-based diet are significantly thinner, says Pasquella, whose clients include Debra Messing, 42, and Sandra Bullock, 46.

Other health benefits include lower blood pressure and cholesterol levels (a major perk for Bill Clinton, 64, who recently adopted a vegan diet and lost weight for Chelsea's wedding). Plus the increase of nutrients like vitamins A, B, and E is great for clearing skin, promoting healthier hair and nails and boosting energy. It's no wonder Lea Michele, 24, who must rehearse for hours on end for Glee, credits her vegan diet for helping her keep up with the strenuous schedule.

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And for animal rights-activists like Natalie Portman, 29, staying away from meat and other animal-based foods is a natural move for them.

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The strict rules of the diet, however, are not for fair weather dieters. In fact, some stars like Julia Stiles and Hilary Swank gave up their vegan ways. "The most important thing to remember is to eat a wide variety of foods so your body will receive all the nutrients it needs to function properly," instructs Pasquella. She advises eating a lot of fruits and vegetables, whole grains, good protein (legumes, beans, nuts, and seeds are all great sources) and healthy fats.

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If you're interested in going vegan but are a little intimidated, try one of these simple switches:

- Participate in Meatless Mondays. Just give up meat and any animal products on Monday and concentrate on plant-based meals.

- Make plants your main course and have meat as the side.

- Swap cow milk out for almond or coconut milk.

- Carry a vegan handbag instead of a leather one. Try Matt & Nat's vegan leather hobos and totes (a favorite of Ellen Page). Each is made from materials like recycled plastic bottles.

- Use vegan beauty products. Urban Decay has a collection of vegan beauty items including their best selling Eyeshadow Primer Potion and 24/7 Glide-On Eye Pencil. Tarte carries PETA-certified vegan cosmetics like foundation, mascara, and primers.