The Fast Metabolism Diet: What Does it Involve?

We'll tell you what the fast metabolism diet involves. It's a diet that promises to help you lose a lot of weight in just one month. Are the claims true?
The Fast Metabolism Diet: What Does it Involve?

Last update: 08 December, 2020

The fast metabolism diet is a dietary plan that promises rapid weight loss over the record time of a month. You could probably put it into the ‘miracle diets’ category. It consists of three phases each week, which we’ll tell you about below.

Before getting into the nuts and bolts of it, it’s fitting to point out this fact. The great majority of diets that claim to have fast and spectacular results can in fact be quite damaging for your health.

In the first place, this is because they aren’t sustainable over the long term. And also, the diets themselves can involve consuming only a low amount of nutrients that could mean your body doesn’t have the essential nutrients it needs later on.

Basic principles of the fast metabolism diet

This dietary plan is based on the idea of avoiding the consumption of ultra-processed foods. This is a sound concept in itself since these foods are proven to be highly damaging to your health. The diet also promotes regular exercise, as well as avoiding conflict and stressful situations.

The other part of the diet is basically eating more. However, that’s not just any food, but rather products that are considered healthy and that have a low caloric value, such as vegetables. In this way, you can eliminate the feeling of hunger, thanks to the extra fiber. This is what a study shows that was published in the journal, Nutrition Reviews.

Diet phases

The fast metabolism diet has three phases each week. During the diet, every four weeks equals one cycle. During the first phase, you can only eat grains and certain fruits. In the second phase, you should include vegetables and alkaline fruits. Then in the third phase, you can start to consume healthy fats.

Red apples glistening on a tree.

The food quantities you should eat aren’t stated, which means you should eat until you aren’t hungry anymore. Foods with a low caloric value such as vegetables should be the priority.

The diet also involves eating five times a day, and not skipping any meals. According to this dietary plan, it’s best to eat every two or three hours.


According to the fast metabolism diet, there are various foods that you shouldn’t eat. The first food is wheat since it’s somewhat difficult to digest and has a high glycemic index. You shouldn’t eat corn either, for the same reasons.

Also, try to reduce your intake of dairy products, since they all contain lactose. This diet’s principles affirm that lactose is indigestible and causes inflammation in the body, although proven scientific research doesn’t take such an extreme stance.

At the same time, you should avoid soy and refined sugars. The first item, because it’s genetically modified. And the second because refined sugars are damaging to your metabolism and health in general. You should also avoid caffeine, alcohol, artificial coloring, and processed fruit juice, which is also high in sugar.

A cappuccino and coffee beans.

Disadvantages of the fast metabolism diet

Since it’s a diet that’s very restrictive, it brings certain risks. The first of these risks has to do with the nutritional imbalance during some of the phases, which lack sufficient proteins and fats.

The second problem is that due to the structure of the diet, it’s difficult to get the lipids you need throughout the diet’s duration. This situation can increase the risk of developing health conditions over the medium and long term.

Also, for people who don’t have an intolerance, it’s not ideal to limit intake of either dairy products or wheat products. In fact, they could actually develop a digestive problem with these foods.

However, this diet does have some positive aspects. For instance, it promotes physical activity and prohibits the consumption of alcohol, as well as some additives, such as artificial coloring.

The fast metabolism diet: a plan to lose weight

Despite the fact that it’s based on healthy concepts, the fast metabolism diet isn’t really the best option to lose weight. It won’t be sufficient to cause long term weight loss, since it’s too restrictive and hard to keep up over time.

Really, if you’re looking to lose some fatty tissue, the best thing to do is to change your habits. This includes increasing your exercise as an essential step. Also, reducing your alcohol intake and consumption of sugary drinks is beneficial. And of course, make sure you eat enough foods rich in proteins and healthy fats.

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.

  • Schnabel L., Kesse Guyot E., Alles B., et al., Association between ultraprocessed food consumption and risk of mortality among middle-aged adults in France. JAMA, 2019. 179 (4): 490-498.
  • Warrilow A., Mellor D., McKune A., Pumpa K., Dietary fat, fibre, satiation, and satiety – a systematic review of acute studies. Eur J Clin Nutr, 2019. 73 (3). 333-344.

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