Everything you need to know about intermittent fasting

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In the previous article we told you what intermittent fasting was and what benefits it had , but do you know when it is not so favorable?

1. Can intermittent fasting be counterproductive?

There are various situations in which intermittent fasting can hinder our goals and will harm us instead of helping us. Some of the most frequent cases in which this occurs are:

1.1. Muscle mass increase phase

Although it is not incompatible to fast and gain muscle mass, it can make the task of the digestive system difficult since, during the stages of gaining lean mass, the calories in our diet must be increased to achieve a caloric surplus.

Sometimes, the amount of food to eat daily can be overwhelming and, if we concentrate so much food in too few intakes to be able to fast, we will be mortgaging our digestive system with very long, heavy digestions, with acidity and that cause lethargy.

In the same way, if we have to do sports during the eating window, it is very likely that we will arrive at training with half-digestion, which will accumulate a lot of blood in the area and will not allow us to express our performance. Sports at its best.

Increase muscle mass

1.2. hyperarousal

The abuse of this strategy along with other tools such as the ketogenic or hypocaloric diet leads our body to a state of overactivation of the sympathetic nervous system; with the consequent excessive release of cortisol and adrenaline that will have a potential power to degrade muscle mass.

Reducing body weight at the expense of muscle mass is going to mean a worsening of body composition and, therefore, it is going to end absolutely all the benefits that we have discussed before. So this loss of muscle mass will cause a reduction in the basal metabolic rate, increased inflammation and loss of insulin sensitivity, among others.

1.3. low metabolic flexibility

Essentially, intermittent fasting should be a strategy that is introduced gradually, without the need to start carrying it out on consecutive days, since the adverse effects that it may cause must first be observed before sustaining its implementation.

The main situation in which it is certainly going to be difficult and counterproductive is in people with very poor metabolic flexibility . Your body is used to obtaining energy from glucose and therefore tends to obtain energy through gluconeogenesis, degrading protein structures and compromising muscle mass.

If in addition to complying with the previous precept, which occurs especially in people with metabolic syndrome, overweight or obesity, fasting is accompanied by a practice of extreme and sudden sports; dizziness and malaise will make their appearance very soon.

2. What to eat during the fast?

As we have remarked, the objective of fasting will be to allow you to suppress anxiety and the attention you pay to food so that no solid intake has a place.

Regarding liquid intake, it is highly recommended to drink plenty of highly mineralized water to promote hydration. In the same way we can consume black coffee without sweeteners, milk or sugar, as well as teas or infusions .


3. How to break the fast

The way in which we break the fast depends on our context. If we have to train in the morning right after finishing the fast, it is necessary to have a first meal abundant in carbohydrates and proteins. If, on the contrary, we train in the afternoon or we are on a rest day, breaking the fast with an intake made up of fat, protein and vegetables would be the best option.

Breaking the fast with an energy resource in the form of fat and protein is the most optimal because it will allow us to extend the benefits that this strategy provides us.

Vegan Keto Powder


Breaking the fast with a piece of fruit is perhaps the worst idea of ​​all since, again depending on the context of the person, the body is very prone to expressing hyperglycemia. While we do not have a scientific study to support this statement, using the Keval+ continuous glucose monitoring HealthSensor system we have observed blood glucose levels higher than 140 mg/dL, 160 mg/dL and 180 mg/dL with fruits such as pears, pineapples or bananas.

So, a good example of food to break intermittent fasting can be the following:

  • Whole free-range eggs
  • wild asparagus
  • Olive oil extracted exclusively by mechanical procedures
  • spices
  • A small portion of fiber bread
egg with wild asparagus

4. How do I know if it is a strategy made for me?

There are three main contexts that we have to know to know if intermittent fasting is going to be productive or not:

  1. Fasting must be closely linked to an organic and somatic need , that is, it must be applied where there is no hunger while fasting and the spontaneous order of the body prevails ; so that there are days when it may be convenient to fast and others when it is not.
  2. Suffering dizziness or brain fog the first few days of fasting is completely normal because the body is adjusting to it, but if it persists for more than a period of one or two weeks, you should definitely rule out this approach to your diet.
  3. Assuming that the total calories, the distribution of macronutrients, sports and rest are adequately adjusted... If anxiety, hunger and nervousness persist during fasting periods; this is definitely not for you.

5. Considerations

All the benefits obtained with intermittent fasting can be achieved with any other nutritional strategy and, therefore, we must understand that its implementation will be given by our biological, personal context and in conjunction with adherence or ease of integrating it into our lives. .

Remark that a less demanding and strict intermittent fasting in hours will greatly facilitate its implementation; understanding that it can be applied both punctually on a specific day and chronically in long seasons.

So, I show you how to get the same benefits of intermittent fasting without using it:

  1. There is autophagy when we do high-intensity sports with weights or have a tangible caloric deficit in the diet.
  1. We can lose weight and abdominal fat by doing physical exercise and carrying out a conventional caloric deficit in our eating plan to allow for an energy imbalance.
  1. Doing resistance exercises with weights, looking for progressive overload, as well as cycling the fats and carbohydrates in our diet increases the degree of metabolic flexibility that we have.
  1. Going for a walk in the morning and exposing yourself to sunlight, as well as consuming carbohydrates at dinner and consuming a melatonin supplement help promote the proper functioning of our biorhythms without the need to limit fasting food.
strength exercise with weights

6. Conclusion

Intermittent fasting is a useful strategy if it allows you to follow your diet naturally and without stress , helping you especially if it is a caloric deficit diet.

Fasting does not mean any progress if it is not combined with high-intensity sports with weights, a balanced and personalized diet, as well as an effective and pertinent rest at night .

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