How the Fast Metabolism Diet Works

If your metabolism is slow, you may want to try out the accelerated metabolism diet to see if it is the right solution for you. Below we will explain what this new diet consists of. 
How the Fast Metabolism Diet Works
Maricela Jiménez López

Reviewed and approved by the doctor Maricela Jiménez López.

Last update: 15 December, 2022

The fast metabolism diet, created by the American nutritionist Haylie Pomroy, will give you better results when it comes to the scale, being able to eat more, and eating better.

If you have spent your life jumping from one diet to another without achieving any of your goals, this may be your solution. This is especially true if you have had to reduce the proportions of your meals, have to count calories, fats or each gram that you eat in order to reach your ideal weight.

In this article, we’ll review everything about the famous fast metabolism diet (FMD). This dietary method will help you lose up to 20 pounds in just 28 days

How does it work? It’s all about eating specific nutrients at certain times in order to reactivate your dormant or slow metabolism.

What is the fast metabolism diet?

Haylie Pomroy designed a perfect, healthy and varied plan so that food isn’t your enemy when it comes to losing weight. Instead, it will become the remedy and the energy you need to accelerate your slow metabolism.

Using this method, she wrote a book titled “The Fast Metabolism Diet” that earned her a spot on the New York Times bestseller list.

In it she states, “You’re going to eat a lot, and you’re still going to lose weight. What you’re not going to do is count a single gram of calories or fats that you eat.

It also ensure that you do the exact opposite, because you will be changing what you eat throughout each week. This is all according to a simple plan that’s specially designed to cause precise physiological changes that will help you accelerate your metabolism.

How does it work?

Basically, the metabolism diet works in three phases. They are divided from Monday to Sunday and have to be repeated for four consecutive weeks.

Next, we will show you the stages by which this diet is structured:

  • Phase one (Monday and Tuesday): You have to eat a lot of fruits and carbohydrates.
  • Phase two (Wednesday and Thursday): You have to eat a lot of animal proteins and alkaline vegetables.
  • Phase three (Friday, Saturday and Sunday): In addition to all of the above, you should add in more healthy fats and oils.

Remember that you should repeat this plan for 28 consecutive days to see results.

Fast metabolism

Do you need to exercise?

You need to exercise in each of these phases. You can divide it among the three phases as follows: a cardio workout, then an anaerobic one and, finally, some type of physical activity that relaxes the body.

This will, without a doubt, help you achieve a more active and healthy metabolism.

Things to keep in mind when doing the FMD diet

Eat five times a day

The basic meals are breakfast, lunch and dinner. You should include two snacks between meals, one mid-morning and one mid-afternoon.

Eat every two or four hours

You should wait a minimum of two hours between meals, but the maximum is four hours. Of course, this rule doesn’t apply when you’re sleeping.

Have breakfast when you wake up

You must have breakfast within the span of the first hour after waking up; you cannot skip breakfast. This is essential when it comes to quickly activating your metabolism.


Make it all four weeks

You must at least make it four weeks following this regimen. Your body needs time to repair itself, which takes a period of at least 28 days.

Respect each phase and its food

You have to respect the order of each stage of this plan and the foods that you eat. Don’t mix, change or swap. That is the only way you will see results.

Say yes to organic foods and no to processed meats.

Forbidden foods

Dairy products

Like most healthy diets, the fast metabolism diet prohibits the consumption of certain foods like:

  • Dairy products
  • Corn
  • Wheat (germinated ones are allowed)
  • Soy
  • Alcohol
  • Refined sugars
  • Caffeine
  • Juice
  • “Light” products
  • Dried fruits
  • Artificial sweeteners

Make sure to avoid fast food and junk food because they contain unhealthy fats, all kinds of sugars and refined flours that are just stored in our bodies.

Health benefits

Haylie Pomroy explains that this distribution of whole and healthy foods aims to help the adrenal glands, reduce stress in the liver and nourish the thyroid. This produces the hormones triiodothyronine (T3) and thyroxine (T4), which are responsible for fast metabolism.

Also, she adds that the fast metabolism diet helps reduce stress and, consequently, the cortisol hormone, which is responsible for the fat in our belly.

She also explains that by using this method, you can also reduce the chances of suffering from several complications such as:

  • Cardiovascular diseases
  • Hormonal problems
  • Hypercholesterolemia
  • Diabetes
  • Arthritis
  • Celiac disease
  • Infertility
  • Thyroid disorders

As you can see, it is an interesting method that you can include in your daily routine.

We suggest that you talk to your doctor before starting it. You should also remember that you need a good exercise routine to make the procedure effective.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

  • McGuinness, O.P., and Shiota, M. (2017). Carbohydrate metabolism. In The Clinical Chemistry of Laboratory Animals, Third Edition, (CRC Press), pp. 745–776.
  • Horowitz, J.F., and Klein, S. (2000). Lipid metabolism during endurance exercise. In American Journal of Clinical Nutrition, p.
  • Mullur, R., Liu, Y.-Y., and Brent, G.A. (2014). Thyroid Hormone Regulation of Metabolism. Physiological Reviews 94, 355–382.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.