By Brierley Wright, M.S., R.D., Nutrition Editor, EatingWell Magazine

4 Celeb Diets to Avoid

Let's face it: Hollywood makes losing weight look easy! Especially with all those toned bodies walking the red carpet this awards season. But if shedding a few pounds is on your to-do list, don't be so quick to follow in the footsteps of your favorite celebs.

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Here are 4 popular celebrity diets to be wary of:

1. Paleo Diet

Megan Fox is rumored to have followed this diet, also called the Caveman Diet. On the Paleo Diet, you're supposed to eat like your ancestors, which means eating a lot of animal protein, "natural" carbohydrates (essentially fruits and vegetables) and some nuts.

The Paleo Diet is high in protein and fat-and there's an emphasis on getting health-sustaining omega-3s into your diet from oily fish like wild salmon, game meats, free-range chicken and grass-fed beef, all of which can be pricier than their farmed or conventionally raised counterparts.

What's interesting about this diet is that its phases are the opposite of most other diets in that they get more restrictive as you progress. For example, at the first level, you get 3 "open" or cheat meals a week, plus what they call "transitional items," such as condiments to flavor food. But when you move to level 2, you only get 2 "open" meals a week and you phase out the transitional items. This type of transition might make it easier to stick to.

What's missing?

Dairy, which is how most of us get our calcium and vitamin D. The Paleo Diet is also low in carbohydrates-and there's research that shows limiting or eliminating carbs impacts your memory and your mood.

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2. Dukan Diet

Dubbed "the French Atkins" this diet reportedly has Gisele Bundchen and Jennifer Lopez among its celeb fans. Kate Middelton and her mother were rumored to use the Dukan Diet to slim down for the royal wedding.

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On the Dukan Diet you only eat lean protein, plus a small amount of oat bran each day, and drink 6 to 8 glasses of water a day in the first phase (attack). In phase 2 (the cruise phase), you introduce vegetables back into your diet, but starchy ones-like potatoes or corn-aren't allowed.

It's not until phase 3 (consolidation) that you're allowed to eat fruit, grains and dairy again, which is why this diet isn't nutritionally sound.

There are some pros to the diet, though: Dr. Dukan incorporates walking 20 to 30 minutes each day into the plan and you're told to eat lean protein.

What's missing?

Key nutrients, such as calcium and vitamin D from dairy, and disease-fighting compounds from fruits and whole grains. Plus there's no mention of portion sizes. In fact, Dr. Dukan tells you to eat as much protein as you like. And ultimately to lose weight you need to eat fewer calories than what you burn. (Get 25 easy tips to help you lose weight and keep it off here.)

3. Raw Food Diet

Demi Moore, Amanda Seyfried and Uma Thurman are all supposed celeb fans of this diet.

A raw-food diet is just that-you eat raw food. Your food can't be cooked above 118 degrees Fahrenheit. So you're eating mostly raw and dehydrated fruits and vegetables and things like smoothies and cold soups that you prepare without heat.

Some raw foodists drink unpasteurized milk and eat cheese made from raw milk, as well as eating raw fish and meats. The big thing to note here is that this can be risky; these foods can carry foodborne-illness bacteria.

There are a small number of studies that suggest there may be some health benefits to a raw-food diet, though: in one study, raw foodists had lower levels of "bad" LDL cholesterol.

What's missing?

If you're not eating any animal-based products like meat, fish, eggs, poultry or dairy you'll miss out on vitamin B12-a vitamin your body needs to transform fat and protein into energy, as well as other essential functions. You also won't get much, if any, vitamin D-and more and more research is showing that adequate vitamin D is important in warding off a host of chronic conditions, from heart disease to cancer.

4. 17-Day Diet

The 17-Day Diet is apparently backed by Dr. Phil. And unlike what its name implies, the entire diet isn't 17 days long. Each phase is 17 days-and that's going to feel even longer when you see how strict the first phase is. In cycle 1, called accelerate, you can eat fish and poultry, as many "cleansing" vegetables as you'd like, low-sugar fruits (but not after 2 p.m.), 2 servings of probiotic foods-like yogurt, sauerkraut, kimchi and kefir-and tiny amounts of "friendly" fats, such as flaxseed and olive oils.

As with the Dukan Diet, the diet becomes more liberal as you "graduate" to the different cycles. For example, in phase 2 you can introduce lean red meat and whole grains, legumes and starchy vegetables.

Overall the 17-Day Diet is strict and, honestly, it'd be hard to follow without carrying the book around so you knew which foods from the various food groups you can actually eat. Also, the total daily calorie allotment from the meal plans provided is too low for some people, particularly if you're active. (Find out how many calories you should be eating here-even if you're trying to lose weight.)

What's missing?

You aren't getting much of a variety of fruits and vegetables-and health experts recommend a colorful variety of produce so you can get a healthy mix of disease-fighting phytochemicals. This diet is also short on grains-and there's recent research that shows eating more whole grains can lengthen your life.

The Bottom Line:

Celebs are fans of these diets because they do work to slim you down quickly. But they work because they are so restrictive-when you cut out certain food groups from your diet, it's hard to make up for those lost calories by eating more of other foods groups. That's why you lose the weight: you're eating fewer calories. Following these diets can help you kick-start your diet and motivate you to transition and stick to a more balanced, healthy diet. But following them for too long means you'll miss out on key nutrients.

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Have you had success losing weight with any of these diets?

By Brierley Wright, M.S., R.D.

Brierley Wright

Brierley's interest in nutrition and food come together in her position as nutrition editor at EatingWell. Brierley holds a master's degree in Nutrition Communication from the Friedman School of Nutrition Science and Policy at Tufts University. A Registered Dietitian, she completed her undergraduate degree at the University of Vermont.





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