weight loss and healthy eating resource

The Fast Metabolism Diet Review

2.90 1 2 3 4 5
Short-term Weight Loss2.9
Long-term Weight Loss2.5
Nutritional completeness3.9
Ease of Use2.5


Fast Metabolism Diet is based on the diet book by nutritionist and wellness consultant Haylie Pomroy. Published in 2013, the book put forward some drastic deviations from conventional weight loss regimen. The 28-day diet plan promises to increase your metabolism and put it into fat-burning mode. It is all about eating well and helping the body burn more fat for energy, rather than starving to lose weight. The diet is presented in a very structured way with separate meal plans prescribed for the different phases involved. There is no severe calorie restriction in any of the phases, but there are several food restrictions, including cutting out wheat and dairy completely.

How the Fast Metabolism Diet Works

Fat Metabolism Diet is a 3-phase diet plan like several other weight loss diets out there. But one major difference is that the phases are not linear, with one following the other, as you generally find in other diet plans. They are cyclical, each of the 3 phases being 2-3 days long and repeating every week. The meal plans for these phases vary as follows:
Phase 1: (Day 1 and Day 2) – High in carbohydrates with moderate amount of protein and low fat.
Called ‘Unwind,’ this phase is meant to put our body at ease, since carbohydrates are easy to digest and are the body’s energy source of choice.

Phase 2: (Day 3 and Day 4) – high in protein and vegetables, but low in both carbohydrates and fat.

This phase is called ‘Unlock’ and is projected as promoting the utilization of stored fat because intake of dietary fats and carbohydrates is severely limited.

Phase 3: (Days 5-7) - High in healthy fats with moderate amounts of carbohydrates and protein. It includes some fruit too. This phase is known as ‘Unleash’ and you are expected to continue fat burning at full swing, both the stored fat and the good fats you are taking.

This phase should ideally coincide with weekends because it allows larger variety and liberal portions of all food groups as compared to the other two phases. Well, that makes Monday the best day to start the Phase1.

Many weight loss diets advocate calorie confusion to keep the body from adapting to calorie restriction. But, you can see, Fast Metabolism Diet is based on nutrient confusion, and prescribes varying amounts of protein, fat, and carbohydrates on different days.

During each phase, the portion sizes depend on how many pounds you want to lose. Contrary to expectation, larger portion sizes are recommended if one has more pounds to lose, and the portion sizes reduce as you progress in your weight loss journey. For example, the basic portion sizes are meant for people who have 20 pounds or less to lose, but if you need to lose more than 20 pounds, you should take basic portion size X 1½. Those who have over 40 pounds to lose should double their intake of vegetables along with 1½ times the basic portion of other foods at every meal.

The basic plan consists of 4 weeks of cycling through the 3 phases, but if you still have extra weight after this period, the program can be repeated until you reach the target weight. You are expected to weigh yourself at the end of each 4-week set and regulate your food intake according to the number of pounds you still need to lose.

Is exercise involved?

Every phase of the Fast Metabolism diet has a prescribed exercise program that corresponds to the eating plan of that phase. For example, in Phase 1 that is usually on Mondays and Tuesdays, cardiovascular exercises are recommended, but not on both days. One of these two days should be set aside for an intense workout, but the other day you should take it easy to allow the body to recover.

In Phase 2, the protein-rich meals should be accompanied by muscle-building exercises such as strength training with weightlifting. Contrary to what one would expect, Phase 3, with its calorie-rich meal plans high in fat and moderate amounts of the other two macronutrients, does not contain any heavy or vigorous activities. Gentle exercises like yoga or a session of body massage are prescribed for these days.

Nutritional profile

The nutritional profile of the diet is a healthy mix of all macronutrients, so it is unlikely that dieters would have any nutritional deficiencies while they’re on this diet. You get sufficient amount of protein, carbohydrates and fats on a weekly basis even though daily intake may vary. Although fruit juices and dried fruit are excluded, one may get sufficient supply of vitamins, minerals, and fiber from vegetables and the fresh fruits allowed in each phase.

The Cost Factor

The Fast Metabolism Diet may appear to be quite cheap since the main expense involved is buying the diet book, which is available for as little as $5 for the kindle version. Even if you want the additional support offered by the cook book by the same author, it doesn’t cost a lot. But the actual cost of the diet hidden; it is in getting all the meals according to the diet guidelines, while avoiding a host of common food ingredients like wheat, corn and soy products, sugar as well as all sweeteners, fruit juices, coffee, alcohol etc.

Do Dieters Lose Weight on the Fast Metabolism Diet?

Those who follow the Fast Metabolism Diet in letter and spirit obviously shed some pounds, but most of it can be attributed to cutting out sugar, processed foods, dairy and grains such as corn and wheat. It is not clear whether the nutrient confusion employed to manipulate metabolism has any great role in effecting weight loss. It is easy to see that the focus is on protein intake, which is generally accepted as helping weight loss by building muscle and increasing metabolic rate even at rest. So the diet may work as well as the many high-protein diets out there, if not better.

Level of Effort

The meal plans look rather liberal at first glance, but the food restrictions take quite a bit of effort to adhere to. The list is long, and you may find it quite impossible to follow it strictly, unless you cook every meal from fresh, basic ingredients. For instance, the basic Phase 2 menu includes 4oz meat or 6oz fish or ½ cup of cooked beans per meal along with unlimited vegetables and a slice of fruit per meal, which sounds like a good deal. But, you have to prepare these items without the use of any oil or fats and the vegetables and fruit have to be phase appropriate. And the only phase-appropriate fruit in this phase is lime and lemon.


Fast Metabolism Diet has several sensible guidelines for healthy eating and optimum nutrition, and it may be worth buying the diet book as well as the cook book. However, it may not produce the quick weight loss results that one would expect from this extremely detail-oriented diet. Although the diet claims to be adaptable to vegetarian and vegan preferences, very few food choices are actually available, even with the concessions on dairy consumption.  The diet may be healthy, but not very practical for busy people. One may have to cook in large amounts to have all the meals ready throughout the week. People with lots of time and a whole lot of patience to cook the meals according to the menu can give it a try.

Read more
User Feedback
13 comments / 91% approval
posted 3 April 2018, 21:27   *
I really like this "diet" and have lost 17 lbs. in three months with, I am sorry to say, some cheating. One of my co-workers lost 36 lbs. in 4 months (no exercise) while his wife lost 60 lbs. I am doing this with another colleague at work, and she has lost 22 lbs. in three months. The challenge is in the planning and, if you work full time, doing shopping and a bunch of cooking--and freezing, on a Sunday. But you can plan ahead for the full 28 days, so you don;t have to slave over the stove every week. I feel healthier and have a ton more energy. I am so glad I did this--and, actually, am still doing this. I took a week off here and there, in between cycle, with minimal weight gain--maybe 2 lbs. My body craves healthy foods these days. I hope anyone who tries this will reap the benefits as much as my colleagues and I have so far. To you!
posted 20 March 2017, 12:28   *
I have been on this plan for 4 weeks with my husband. It is working so well that we are going to do another 4 and go on the recommended maintenance eating plan after. This article has a mistake where an example Phase 2 meal is explained. It's under "Level of Effort".
posted 12 March 2017, 15:40   *
I have been on the diet for almost 7 weeks and have only lost 10.2 lbs........however, I am never hungry and am eating real, healthy food. I also have one of those worn, diet stressed out bodies that do not respond well to anything "diet". One thing about the starvation diets is that you saw quick results, the FMD is not "fast" in the weight loss area and I always feel so disappointed at the beginning of each week when I weigh in as I'm sticking to the program 100% but the scale does not reflect this. I've lost 10.2 lbs so far which is better than nothing so I will stick with it hoping as my metabolism gets "fixed", better results will show in the future. I do have a question to anyone who can help me. The FMD book states there is a "Super-Simple Diet Option" which I want to incorporate in May when a group of my friends are going to Vegas for a week. We'll be in a hotel room with no fridge available so I want to order some of Haylie's Phase specific Breakfast shakes and the phase specific food bars. However, when I read any Q&A or FMD comments, the answers say the food bars are for those on maintenance only - which is different than in the book on pages 235-238. Can anyone tell me if there is really "phase specific" food bars. Also........is anyone else experiencing a very slow weight loss in comparison to some of the profiles in the book that indicate 20-86 lbs lost? Thank you, Nancy
posted 20 February 2017, 07:32   *
Pros: Fast weight loss (I'm down 6 pounds the first week) You eat A LOT so you rarely feel hungry. Each phase lasts only a couple of days so if it's not a favorite, it moves by quickly. You drink a lot of water. This is something I've been trying to work on anyway. The first day or two are tough if you're not used to it. By the end of the week I'm drinking more than I have to. Cons: LOTS of prep time. a bunch of people said you can't do it if you're busy. You can. It just takes a lot of work. I work full time and have 2 kids in activities I'm running here and there. I just cut out time during each night to pack everything for the next day. Very restrictive. This makes it impossible to go out to eat or have that one "free" meal a week that many diets allow for. Leg pain: This sounds strange, but during the first week I noticed leg pain... an overall achiness. One day it was bad enough I took ibuprophin for it. I had this both times I was on the diet. I assumed it was a kind of result all the bad stuff leaving my body. Overall, if you're looking for fast weight loss without the hunger, this is the way to go. If you like flexibility, I'd stick with something else.
Pam M.
posted 27 January 2017, 02:32   *
Love this diet (hate to call it that). The word diet sounds like "torture, hunger" but NOT with the Fast Metabolism plan. It works! My husband and I did it together. I studied the book ( which is so interesting and educational) and purchased the separate cookbook. Simply picked the recipes, made my grocery lists ahead of time and got to it. My husband would chop and I would cook. We have never cooked together and it was great fun and less work! He lost 23 lbs in the 28 days and I lost 19 and we're not finished losing yet! When you start this new way of eating for the first time, the first couple days are the hardest as your body is withdrawing from all the junk and sugar so you may feel sluggish or experience a mild slight headache. It's proof that what you've been eating has been bad bad bad. By the fourth day, bam! You feel better, different, and more energetic. The food is delicious so don't be afraid of cooking the old fashioned way with real seasonings, garlic, cabbage, coconut oil...it becomes the new normal. Then our sleep....wow, good, solid, deep, restful sleep straight through the night. Amazing. Do it in the phases as instructed and you will see great results in the way you look and feel. You will save $$$ cooking delicious meals at home rather than fast food or eating out. You will eat lots of food and I mean delicious satisfying food. I've done all of the diets. THIS ONE IS THE BEST AND TRUEST WAY TO EAT FOR the REST OF YOUR LIFE. We both love it. And, our kid's are watching, tasting and learning along the way, on how to cook and eat healthy.
posted 23 January 2017, 18:22   *
First the eating plan for the Fast Metabolism Diet is NOT low-calorie, my husband would never agree to a low-cal anything! There is actually so much good food, it's difficult to eat it all. This is the second time my husband and I have been on this eating plan...we both lost weight so easily the first time around. We ate exceptionally well, dropped bad eating habits, gained a lot of energy and felt great! We're excited about starting again this week, and remembering how much food we have to consume!! The more you eat, the more you lose! My husband is looking forward to all the home-cooked meals and losing a few pounds in the process. The only drawback is the prep time...but once we get the hang of the menu items in each phase again, that gets easier and easier. You just have to plan ahead, and cut a lot of veggies!!
posted 9 January 2017, 15:14   *
I lost 19 1/2 lbs in the 28 days. I did follow the plan to the letter as I didn't think it was possible for it to work.
posted 3 November 2016, 10:17   *
first off fast metabolism diet is NOT essentially a low calorie diet so that diminishes your opinion somewhat. i like many other people began the diet to lose weight and feel healthier. i have been on dozens of diets and the all left me tired, cranky, and starving hungry most of the day. this diet did none of those things. after one month i still did not see the scale move significantly and i was feeling discouraged yet again. i then joined the support group and found that i was not the only one having a sluggish start. i was told that i was not eating enough!!! what??? not eating enough??? so i upped my intake of listed foods and the weight began to drop off. i feel great even if my lose is not as quick as others but my metabolism had been down for so long that it needed to be healed before i started to drop weight. if i was to list a down side i would say the diet is not easy in the beginning and if you don't meal plan you will not be successful, so join the support groups and learn from others that have been there prior. prepare your weekly meals on Sunday and keep it simple. if it can work for me it can work for anyone. plus it's a wonderfully, healthy to eat even if you are not looking to lose weight.
posted 29 August 2016, 14:38   *
I started this program and found it extremely easy to follow. She clearly explains why she wants you to eat the way she has her program set up and there is a very clear list of foods all together. I keep a copy with me when I go shopping. She also has menus and recipes all right there if you do not want to create your own. I was stuck this year and nothing worked. The food is regular items found at Marcs and Walmarts- no need to purchase anything fancy. Simply write out the phases and plan a bit ahead to make sure you have plenty of vegies, protein, fruits and grains. Every shopping and meal plan takes some effort even without a program. She promotes healthy foods and how to reset your metabolism so you will drop the belly fat and stop storing fat instead of burning it. There is no need to be hungry. People are coming up to me and saying they do not recognize me. They also say how healthy I look and that my skin glows. I feel great and have energy and am so motivated to keep going. I lost 14.5 pounds in 28 days and 5 inches from my belly area- despite making some big mistakes in Phase 3 and a small mistake in Phase 2. Even more motivated with the results. Lots of coworkers on this and everyone excited and happy. Friend who told me about the book lost 20 pounds the first month and 12 the second and has kept it off with normal life and even going to parties. Very happy to have found this book- but you do need to read it.
posted 9 July 2016, 06:59   *
I've lost 10 lbs in 12 days but I've had some very frustrating days. Several family members did this diet with good results and loved it so I thought I'd try it. For me it's not user friendly. I can't buy some of the ingredients in our local grocery store, there's lots of prep work and I'm constantly referencing the books to see what I can and can't eat. Phase 2 is the most frustrating for me. However, in spite of being frustrated at times, it is a healthier lifestyle change and I'm eating less processed foods. I'm hoping that I will be less frustrated as I learn to navigate the diet plan. This past week I've frozen some of the left over meals to use next week so that should be helpful. My dear husband has been very supportive. He eats the dinners I prepare without much complaint, but I do usually fix different or additional sides for him. If I were still employed I don't think I'd be able to even make a good effort toward this plan. But retirement allows me to give it a try. I'm committed to doing the full 28 days. I don't expect to lose the entire 50 lbs I need to lose, but I don't know if I'll repeat this diet again.
posted 10 June 2016, 18:14   *
This diet was the answer for me. I started the 28 day program on January 11, 2016 and by June 3rd i had lost 31lbs. I still have a few pounds to go. I am 62 years old and had little hope that it would work for me. I have no side effects. In my case I saw no disadvantages. The hardest part is starting out, after that no difficulties. Since i was a compulsive eater of starchy carbs, i am amazed. I would recommend it and i have already done so to several people.
posted 3 June 2016, 20:25   *
I lost 4 lbs over 3 weeks. Very disappointing results. I believe the theory and the author's interpretation of foods and their relationship to weight gain/loss, but did not find the diet to be successful for me.
posted 15 May 2016, 00:09   *
I found the Fast Metabolism Diet to be very good. The variety and amount of food you are allowed is both satisfying and filling. I don't have bad cravings, I have alot of energy, I sleep well, I feel very good on it. I wanted to lose only 20 pounds and have lost 15 pounds in six weeks. I workout 5 times a week with weights and cardio for an hour a day. My husband is on it now too and has lost 10 pounds in 3 1/2 weeks. I highly recommend this diet to anyone. If you write out what you eat every day you will have a good menu to follow on your next 28 day cycle making your food preparation easier than the first time around.