When it comes to dieting, Hollywood celebrities will try almost anything to drop a few pounds, all the while raving about how their new parsley and pimento diet has helped them fit into that red carpet dress. The question is: Do these diets really work, are they safe and are they achievable for the common person?

Mariah Carey: Purple food diet
When Mariah Carey found out that purple foods (eggplant, plums, beets) contained powerful antioxidants that help reduce the formation of wrinkles, she announced to the world that she was going on a strict purple food diet and began eating only purple meals three days a week. 

"While resveratrol, the purple pigment, is touted as the best anti-aging antioxidant, eating only purple foods is hard to do," says Charlene Chen, a registered dietitian in Vancouver. "It would be best to emphasize dark green, dark orange and dark purple fruits and vegetables to get as many vitamins and antioxidants as possible, but the best way to prevent wrinkles is by wearing sunscreen, sleeping a full eight hours a night, a healthy diet, regular exercise, and good stress management."

Verdict: Safe, but unnecessary.

Beyoncé: The Master Cleanse
For her role in the Oscar-nominated film Dreamgirls, Beyoncé lost 20 pounds on The Master Cleanse. The cleanse, which was not originally meant for weight loss but rather the treatment of ulcers, is a non-food diet where the participant drinks a concoction of fresh lime or lemon juice, maple syrup, and cayenne pepper mixed with water six to 12 times a day, along with an herbal laxative tea taken twice a day.

"Though lemons have vitamins and minerals, which are useful to the body's metabolism, the body needs a daily intake of protein, carbohydrates, and fat," says Chen. "This is a starvation diet that will force the dieter to lose muscle mass and gain back all the weight once the diet is over."

Verdict: Unsafe

Madonna and Gwyneth Paltrow: Macrobiotic diet
Straying from traditional diets, celebs like Madonna and Gwyneth stay slim following a strict macrobiotic diet, which is a fish and plant based diet centered on Japanese cooking principles.

"Although it takes more effort in planning to ensure one gets sufficient nutrients," claims Chen, "it is a safe diet that emphasizes grains as a staple, less refined foods, local ingredients and fewer animal products."

Verdict: Safe and nutritious.

Page 1 of 2Jaime Pressley: Cabbage soup diet
The My Name Is Earl is star lost the first 10 pounds of her pregnancy weight on the cabbage soup diet, eating only cabbage soup and a small amount of vegetables for one week.

"By eating only fibre and water from cabbages and similar vegetables," says Chen "one basically starves the body – like the effects of The Master Cleanse – and forces the dieter to gain all of the weight back after the diet is over."

Verdict:  Unsafe

Jennifer Aniston: The Zone
When Aniston first landed a part on the über series Friends, she quickly went on The Zone diet to lose some extra pounds for her new job. After seeing how this low carb, high protein diet – based on the scientific principle that too many carbohydrates lead to high insulin production, which leads to weight gain – helped her spiff up her body and maintained her goal weight, she decided to make The Zone diet a life choice and continues to Zone to this day.

With calorie control based on less than 500 calories per meal and less than 100 calories for a snack, The Zone is a perfect way to slim down and keep the weight off.

Verdict: Safe, healthy and relatively easy.

Reese Witherspoon: Baby food diet
Reese credits her fit body to running three to four miles daily, snacking on baby food and eating only one adult meal daily.

Though the texture and the thought of eating baby food may be unappealing, Chen believes that as long as both carbohydrates and proteins are being consumed, eating baby food is a healthy way to snack and can aid in weight loss

Verdict:  Safe but unappetizing!

Claudia Schiffer: Light morning fare
To stay svelte, Claudia Schiffer eats nothing but fruit before noon, has a light dinner of salad and steamed vegetables, and snacks on tomato juice, black grapes and herbal tea.

Although this diet sounds good on paper, Chen believes there is one major flaw in Schiffer’s plan. "One should eat within two hours of rising to ensure proper fuel is supplied to the body.  During nightly sleep, we deplete our supply of fuel and water, and morning is the time to rehydrate and refuel. Studies have shown that dieters who achieve successful, permanent weight loss do so by eating a light breakfast – usually cereal and low-fat milk – as a principle of appetite and metabolic control."

Verdict: Safe but not realistic for weight loss.

Although most of these options are, well let's put it bluntly, crazy, the facts remain the same: as long as healthy food is being eaten with both protein and carbohydrates there is a good chance that weight will be lost in a safe way. But when it comes to the common person trying to look as svelte as our favourite celebrities, Sarah Michelle Gellar says it best: "Look, it's crazy for people to try to be as thin as we are. We have personal trainers and personal chefs. It's our job to look this way."

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