How did Jessica Simpson manage to slim down while keeping her curves? The secret is her regular workouts with celebrity trainer Harley Pasternak and following his 5 Factor Diet. The plan calls for five meals a day, with five elements per meal (protein, good fat, healthy carbs, fiber, and a sugar-free beverage).

Rockin’ Robin

Though this popular plan promises you’ll lose 21 pounds in 21 days, radio personality Robin Quivers lost nearly 25 following the Martha’s Vineyard Diet. The strict diet involves consuming juice, tea and soup and having regular colonics and spa treatments.

Oh Oprah!

For years we’ve watched Oprah’s show — and her weight. But with the help of trainer Bob Greene the talk show queen has finally found a diet that works for her. She eats a diet rich in lean protein, fruits and vegetables and limits alcohol, refined carbs and sugar. She also won’t eat close to bedtime.

Kirstie Alley

There’s nothing secret about Kirstie Alley’s weight loss: The once svelte star of ‘Cheers’ has been the face of Jenny Craig’s diet plan since 2004. Alley is said to have lost more than 55 pounds on the program. She’s even written about the experience in a book called ‘How to Lose Your Ass and Regain Your Life.’

Beyonce

Beyonce may be known for her curves, but the star has said she lost 20 pounds on the ever-trendy juice fast, the Master Cleanse, for her role in ‘Dreamgirls.’ The fad diet (also called the Maple Syrup Diet) consists of drinking a concoction of syrup, lemon juice, water and cayenne pepper.

Jennifer Aniston

When she starred on ‘Friends,’ Jennifer Aniston reportedly turned to the Zone Diet. On this plan, Jennifer would aim to have her diet consist of 40 percent carbohydrates, 30 percent protein, and 30 percent fat. The Zone’s founder claims this ratio will rev your metabolism.

Jennifer Lopez

J.Lo has said that her only diet is a strategy of eating anything she wants in moderation. However, it has been reported that when Jenny wants to drop some weight, she cuts out the carbs in a strategy similar to the Atkins Diet.

Madonna

How does a middle-aged singer with two children maintain such a phenomenal physique? In addition to punishing daily workouts, Madonna adheres to a strict macrobiotic diet, which is based on the idea that food affects health, well being, and happiness. The diet focuses on whole, unprocessed foods and is low in fat, high in fiber and rich in vegetables and soy.

Jessica Biel

To get into fighting shape for ‘Blade: Trinity,’ Jessica Biel followed a strict diet that banned sugar, dairy, flour and salt. To keep her metabolism revved up and to get her through an intense workout schedule, Jessica has said she would eat several small meals every few hours, similar to the 3-Hour Diet.

How she stays fit

Jennifer Aniston keeps fit by using a sensible diet and workout plan. Aniston has used the Zone Diet for many years, showing off the good results on her TV show. The Zone Diet helps its users lose weight by ensuring balanced nutrition. The Zone allows meals to be made up of 50% carbo, 30% protein and 30% fat in controlled portions.

As for her workout plan, Aniston uses both cardio workout and yoga to keep in shape. Like most celebrities, Aniston enlists the help of a yoga instructor to help her with the moves. Aniston says yoga not only helps her trim fat, it also keeps her muscles long and lean. She also credits yoga for her body and mind total makeover.

As for her other fitness regimen, Aniston owes much of her buff bod to professional trainer Rachel Kaehler, who is also responsible for other famous clients such as Julia Roberts and Sarah Jessica Parker. Kaehler’s upper body workout routine has helped Aniston keep her arms and shoulders red carpet ready and fit to show off in strapless gowns. Kaehler maintained a workout schedule with Aniston in 3 to 4 times a week sessions.

Aside from changing her diet, Angelina Jolie also had to undergo kickboxing training, yoga, and street fighting. Soon, she had more feminine curves, and was stronger than ever before.

Now the UN ambassador and wife of Brad Pitt who gave birth to Shiloh, the baby with photos that’re worth millions of dollars was reportedly getting thinner and thinner because of her encounter with people in famine-stricken countries and her mom’s death .

Angelina confessed at the New York premiere of her new film A Mighty Heart on Wednesday: “I’ve always been lean and this year I lost my mom and I’ve gone through a lot.

Those reasons sounds quite valid but there’s a lot more reason as to why Angelina Jolie will remain that painfully thin for quite some time, having four kids (three adoptive Maddox, Zahara and Pax and one biological - Shiloh Nouvelle) can’t be discounted either.

However, again, there’s no excuse to forgetting about your health, especially for celebrities like Angelina Jolie because there are fans looking up on her.

Soon, Kirstie Alley lost seventy-five pounds, appeared on Oprah’s show wearing a bikini, and even had her own show to host. She became a spokesperson to Jenny Craig, a stage she now shares with fellow actress and friend Valerie Bertinelli, whom she referred to the program. Kirstie Alley is undoubtedly one of the most famous weight-loss celebrities, and she will always be remembered as the woman who dared to bare her leaner body – and perhaps inspired a legion of fans to go through their own weight loss programs.

How she keeps fit? Electra keeps a diet and workout plan, a regimen she maintains to keep in shape and also to tame her stomach, a part of her body she is not too crazy about. Lately, she has focused her energies into producing a fitness regimen to help other women keep fit and healthy Carmen Electra-style.

Electra’s fitness regimen centers around her workout videos, titled ‘Aerobic Striptease’ and ‘Fit to Strip’. Both videos feature how-to steps using strip teasing dance moves to keep in shape. While the entertainment purpose of the tape is not lost to its users, Electra swears by its effectiveness. It features the same moves that Electra uses herself to keep her body in great condition. This was the product of her collaboration with DVD producers who saw the potential in her burlesque show.

Electra is promoting her DVDs to help women lose weight and have fun at the same time. The DVDs feature both exercise and striptease routines. The videos show Electra and two other women as they dance a series of choreographed moves. The routine, Electra says, are something that women will find enjoyable to use and benefit from at the same time.

Then she got married and had two kids and even tried to drop off the public eye. The many times we’ve gotten a glimpse of Britney were through her short-lived reality show and the ever-present paparazzi pictures. Baby weight still hounded her at the time but she has since bounced back to prepare for her much-awaited comeback.

From being the semi-sedentary Ex-Mrs. Federline, Britney is slowly trying to regain her pre-baby body by enlisting the help of her trainer, Bobby Strom. Her regular workouts consist of aerobic and cardio exercises to help burn off calories and shed off fat. After living a life of less physical activities than she was used to, Britney is building her muscles once again through these workouts.

Do you know that aside from the basic diet of simple, healthy meals including plenty of fruits, low-fat yogurt, and nuts, Britney, on top of her busy, active, and hectic lifestyle allots about 360 minutes a week just for her routine workout? That is at least four days a week, 90 minutes a day. She could spend up to 10 minutes just warming up in a stationary bike or a treadmill as her initial cardiovascular exercise and then do crunches, leg raises, and bicycle twists up to a maximum of 600 awesome counts! Now, that explains her amazing abs. She is also into Yoga. This way, she does not only keep her body fit by doing a lot of stretching, she also achieves good blood circulation, tranquility, balance, and control over her body and mind.

She is also known to do a lot of dancing to help maintain her footwork and as a means to keep up to date with the latest dance moves. When working with her choreographer, Britney was reportedly encouraged to sing to her songs ‘full out’ while using the treadmill, to help maximize her lung capacity and burn extra calories. Her recent pictures have shown that her routine seems to be working, showing a more fit and healthy-looking Britney Spears.

Eva Longoria is petite but fit, and she keeps her figure through kickboxing sessions. A student of kinesiology, Longoria knows how the human body responds to certain movements, and she isolates muscles by cardio training, weight training, and alternating days of yoga. To tighten her bottom, she does leg presses, squats, and lunges. Mind you, Longoria is not on any strict diet. She simply eats a lot of fresh fruits and vegetables, but she still has time for the occasional pizza slice.

Teri Hatcher is still fabulous at age forty, and she keeps her figure slim by toning her body in the sauciest, naughtiest way possible: striptease classes. Pole dancing is now being offered at many gyms all over the world: it not only teaches a woman how to isolate and tone certain muscles, but it empowers a woman because it makes her more comfortable with her body.

The average pole dancing session will entail about an hour of stretching muscles in the buttocks, arms, and chest, then half an hour of routines using the pole. Hatcher takes these classes twice or thrice a week. In addition, she plays golf and hikes regularly.

Katherine Heigl drinks teas rich in antioxidants, and eats potatoes and meat; she also eats smaller snacks instead of eating three full meals a day. She has a hard time eating fresh fruit, but she occasionally indulges in a kiwi or pineapple. For weight control, Heigl simply trusts her instincts: she eats whatever she feels will make her healthy. Although she was once skeptical of work outs, her experiences have taught her to take up exercise to up her mood and make her ready for the camera. She exercises on an elliptical machine or hikes around West Hollywood, where she lives.

In addition to walking, Heigl spends time on the yoga mat, where she concentrates on flexing her abdominal muscles and taking out the stiffness in her leg and back muscles. Stress can make her eat uncontrollably, so she copes with the demands of the Grey’s Anatomy set by reading novels or sketching. She also eases herself to sleep by warming up before a fire or soaking herself in a warm bath.

Often hailed as a life-sized Barbie, Jessica Simpson is greatly admired for her blond locks, baby blue eyes, smooth golden skin, and curvy figure.

Although the whole world already knows that ProActiv is her facial beauty secret, not everyone is in the know about her diet and workout tips.

If you’d like to dazzle men with a curvy figure like Jessica Simpson’s, the actress-singer and ex-Mrs. Lachey has shared a few of her secrets.

Jessica Simpson admitted to having followed the Atkins diet once but the tandem didn’t work out. “Atkins really messed me up mentally. I was so starved for carbs, I binged on them.”

During the filming of Dukes of Hazzard, she worked with Michael Alexander and followed the Don’t Eat Crap Diet. For the three months Simpson was shooting the movie, Alexander made sure the actress only ate broccoli and asparagus, seared fish, and grilled chicken. Desserts, extra sugar for iced tea, and bread baskets were a no-no. For Jessica Simpson’s exercise routine, she had to perform half an hour of cardio, 1 hour of weights as well as squats and lunges. Light weight dumbbells were only used.

Nowadays, however, Simpson is working with Harley Pasternak, a favorite celebrity trainer. Her main diet is composed mostly of vegetables, grilled chicken, steak, and fish. She’s allowed one day a week to eat anything she wants. For workouts, she has to do twenty sets of three-step lunges and squats and thirty to forty-five minutes of cardio. All in all, she works approximately two hours a day, five times a week.

Although Jolie admits that Croft is the role closest to herself, playing her was one of the hardest things she has ever done. “It was such a challenge physically,” tells Angelina, who prepared for the role by following a training regime that included kickboxing, canoeing, street fighting and yoga. “A special diet also helped me shape my body. I ate steamed sea bass or steamed beef and vegetables, and I had no sugar and only drank soy milk.” Angelina had lost weight from overwork and was glad the training and healthy diet helped her put back on a few pounds of curves.

“I’m all for curves on a woman, and feeling sexy,” she says, “and I never felt healthier or stronger than during the filming of this movie.” Jolie performed almost all of her own stunts in “Tomb Raider,” which include sword fighting, spear throwing, dog sledding and bungee jumping. For the bungee-jumping sequence, she went through three months’ training. “The most difficult thing was learning how to do bungee ballet,” she recalls. “It took a while to learn how to work with the harness.”

When Angelina Jolie was married to husband Billy Bob Thornton, they were really focused on cleaning up their acts. Angelina said, “No more smoking or drinking, and a sugar-free diet. They want to be really healthy before they embark on having children”.