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Fast Metabolism Diet: What do experts say?

In the best-selling book The Fast Metabolism Diet, celebrity nutritionist Haylie Pomroy shares her secrets that have helped thousands of clients rev up their metabolism and lose weight. At its core, the Fast Metabolism Diet uses real whole foods in varying combinations to "keep your metabolism guessing" and get it to work harder and faster. So what do the experts have to say about this popular diet?

What is the Fast Metabolism Diet?

The 28-day Fast Metabolism Diet consists of three phases that are repeated for four consecutive weeks:

  • Phase 1 (Monday–Tuesday): Unwind stress and calm the adrenals with lots of carbs and fruit.
  • Phase 2: (Wednesday–Thursday) Unlock stored fat and build muscle with lots of protein and veggies.
  • Phase 3 (Friday–Sunday): Unleash the burn (hormones, heart and heat) with all of the above, plus healthy fats and oils.

Those who have tried the diet say it's not really a diet at all, but a return to a healthier way of eating. The Fast Metabolism Diet incorporates plenty of fruits, vegetables, proteins, legumes and lots of water (half your body weight in ounces every day!) and forbids wheat, corn, dairy, soy, refined sugar, caffeine, alcohol, dried fruit and fruit juices. The book provides daily guidelines (the number of proteins, veggies, fruits and grains to be eaten at each meal and snack) as well as sample meal plans and several recipes.

Expert feedback on the Fast Metabolism Diet

Sounds good, but does the Fast Metabolism Diet make good nutritional sense? We asked three registered dietitians to give us their take on the program. Here's what they had to say:

Sarah Waybright, registered dietitian and owner/founder of WhyFoodWorks, LLC, appreciates the diet's focus on eating real whole foods. "Americans simply eat way too many refined, nutrient-poor carbohydrates. Sugar consumption alone went from 110 pounds per person annually in 1950 to 150 pounds per person in 2000!" Waybright says the diet's ban on wheat, corn, dairy, soy, refined sugar, caffeine, alcohol, dried fruit and fruit juices eliminates many unhealthy options. "Replacing them with nutrient-dense options like fruits, vegetables, lean protein and fiber-rich whole grains offers a diet that's high in micronutrients for fewer calories."

So how does the Fast Metabolism Diet compare with the many prepackaged "diet food" programs out there? In general, says Waybright, these programs may not be as satisfying or have the same quality of vitamins and minerals as the whole foods that the Fast Metabolism Diet recommends. Reduced-fat products often add more sugar or sweeteners to compensate for the flavor difference, she adds. "The FMD diet seems like a new way to think about an old concept: eating a diet of whole foods."

Registered dietitian-nutritionist Jessica Lehmann, who teaches nutrition at Arizona State University, agrees. "It's best to learn how to plan a balanced, moderate, nutrient-dense diet that's based on a variety of whole, unprocessed foods and that fits your own individual needs and dietary preferences."

And what do these dietitians have to say about the significant quantity of water the Fast Metabolism Diet recommends? Drink up! "Drinking water before a meal is an easy way to fill up and reduce calorie intake," says Lehmann. A 2010 research study published in the journal Obesity took two groups of overweight adult subjects on a low-calorie diet and gave one group a 500 milliliter (17 ounce) drink of water before a meal. "Over a 12-week period, the group that drank water before the meal lost 44 percent more weight than the control group who did not drink the water."

In the Fast Metabolism Diet, Pomroy says to consume organic produce whenever possible to stop additives, preservatives, pesticides, insecticides and hormones from slowing down the liver's job of burning fat.

LifestyIe and wellness consultant Jasmine Jafferali, MPH, ACE-CPT, agrees that avoiding artificial sugars, dyes and preservatives and eating organic produce is ideal, but says eating organic for everything may not work for everyone. She recommends following the Dirty Dozen list for buying organic produce, if on a limited budget.

Lehmann recommends choosing organic whenever possible, saying it's important to stay away from chemicals that affect so many pathways in our bodies, including the metabolic reactions involved in burning fat. However, she warns against using the "organic" label to justify bad food choices. "I'd much rather see someone snacking on a bowl of conventionally produced vegetables than a handful of organic cookies!"


Have you tried the Fast Metabolism Diet? Share a comment and let us know how it's going!

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