Body Beautiful: The Latest Celebrity Diets

Beyoncé made headlines back in December when she went vegan for 22 days, following the fitness plan of Marco Borges. "She is all about health and wellness. She just wants to feel good," Borges told E! Though the star isn't fully vegan anymore, she still eats a mostly plant-based diet with fish, says Borges.

How does a mother of six stay so svelte? Angie follows the ancient grains diet, adding grains, seeds, and nuts including quinoa, millet, chia seeds, spelt and buckwheat to her meals and snacks whenever possible. Beauty benefits of the plan include glowing skin and shiny, healthy hair.

Organic, local, gluten-free and vegan, the Sakara food plan delivers meals straight to your home or office. It's up to you to decide if you want a one-day cleanse, a five- or 20-day plan, or a three-month subscription. Whitney Tingle and Danielle DuBoise founded the company in 2011 to "promote balance in all areas of life...true health means you're making the right choices for your body because you want to, not because you have to." Customer Iman says of the program, "Danielle and Whitney make quite a pair and all they want is for women to feel good in their bodies. They are sharing their passion for great food, and great style, with the rest of the world."

Sakara Organic Meal Delivery, from $99, sakaralife.com.

Back in January, Posh tweeted a picture of the cookbook Eating the Alkaline Way. "Love this healthy eating cook book!!" she enthused. Clearly, it loves her back; Beckham has maintained her signature svelte frame with a diet rich in fruits and vegetables that curtails consumption of acid-forming foods like dairy, pasta, meat and fish. The goal? To keep the body's pH balance between 7.35 and 7.45. Other famous fans of the diet book, penned by Natasha Corrett, the stepsister of Sienna Miller, include Jennifer Aniston, Kirsten Dunst and Gwyneth Paltrow.

Eating the Alkaline Way: Recipes for a Well-Balanced Honestly Healthy Lifestyle, $16, amazon.com.

Megan Fox is a huge fan of celebrity trainer Harley Pasternak's 5-Factor Diet, which Eva Mendes, Alicia Keys and Jessica Simpson also swear by. The program encourages dieters to cook with five ingredients or less and follow Pasternak's rigorous exercise regime.

The 5-Factor Diet, $12, amazon.com.

To shed her baby weight, Drew Barrymore has been using celebrity nutritionist Kimberly Snyder's Beauty Detox Solution. The program, of which Fergie is also a fan, encourages a plant-based diet and lots of juicing.

The Beauty Detox Foods, $13, and The Beauty Detox Solution, $12, barnesandnoble.com.

Celebrity trainer Tracy Anderson recently launched a nationwide food delivery program that guarantees weight loss when combined with Anderson's workout methods. With a menu featuring options like Provençal eggs with eggplant zucchini and coconut flan with mango passion fruit sauce, as well as a separate program for vegetarians, it's no wonder Gwyneth Paltrow and Jennifer Lopez are hooked.

The Food Program by Tracy Anderson, $54.95 per day for 14 days, foodprogrambyta.com.

Christina Aguilera slimmed down with The Fresh Diet, a home delivery meal plan created by a Le Cordon Bleu-trained chef. The program touts a vast menu, with meals like multi-grain strawberry pancakes, mango-stuffed pork loin and key lime cheesecake landing on hungry dieters' doorsteps twice a week.

The Fresh Diet, $60 per day for seven days, thefreshdiet.com.