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Yes, intermittent fasting can be scary

After the first articles I read about ways to do intermittent fasting and its benefits, I thought it would be very difficult to convince the people that I always recommended eating every three hours. “And now, how to explain the advantages of lengthening the intervals, each time greater, between meals?”.

At the same time, it seemed impossible to implement on myself. I have always been that person who ran out in pain to do clinical exams in the morning, thinking that I was not going to be able to fast for long, afraid of feeling bad, without strength and with headaches. But when I realized what to do and how to do it, I gave it a try and was hooked. My energy level during the fasting period increased and, consequently, my professional performance as well. And it is, of course, a great advantage, since it reduces the need to search for food to keep energy levels stable.

Nutrition sciences, despite not being recent (the first degree in Nutrition in Portugal started in 1987), have evolved a lot in the last ten or fifteen years and this is due to investment in research. Intermittent fasting is one of the “gifts” that science has given us to achieve better health results through food.

We can define intermittent fasting as a strategy to manage periods of fasting (or abstinence from hypercaloric foods) with periods of eating, which we rightly call “eating window”. Strategies for this practice have become very popular in recent years and are associated with clinically significant weight loss, improvement in insulin resistance and markers of inflammation.

They exist various protocols that require more or less hours of fasting:

• periodic fasting, which involves caloric restrictions for five consecutive days, a few times a year;
• Time-restricted fasting the best known is 16-8, in which the feeding window will be eight hours, during which you can eat the same amount of food as in a normal day (although, as a rule, this does not happen). On this 16-8, the fasting window will be 16 hours (and can reach 18);
• Fasting from 22 to 24 hours which involves only one meal a day, but cannot be done on consecutive days (and at most once or twice a week);
• I fast on alternate days, which are a very aggressive restriction, in which calories are limited on certain days of the week. It is less studied in terms of benefits and the best known method is the 5-2, in which calories are restricted to 500kcal two days a week and the rest of the days food is free.

The most common (and most studied) type of intermittent fasting is the 16-8 hour restriction. in which, classically, breakfast or dinner is omitted to complete the interval of hours. It is important that this 16-hour fast is not done every day of the week, maintaining at least two days in which there are 12 to 14 hours of restriction (which is actually already considered fasting, but less).

To benefit your health, there is no magic number of times a week to do it. You can do it just once a week or more. The really important thing is that it does not cause stress to our body.

If you are thinking of following this dietary strategy, keep these points in mind:

• Radicalism doesn’t work. Yes there are ominous symptoms such as cramps, headaches or even very hungry when you start eating it is because it is not working and the strategy should be re-evaluated.
• THE hour count it should always be done between the end of the last meal of the previous day and the beginning of the first meal of the following day.
• It is extremely important that during the fasting period you hydrate very well with non-caloric liquids???????? Water or tea/herbal teas, as long as no sugar or sweetener, milk or any other food is added. You can also have coffee or decaf.
• Intermittent fasting is an essential strategy clinical orientation???????? It should be advised by a nutrition professional, since there are some contraindications that must be identified, such as individual intolerance, pregnancy, type 1 diabetes and kidney failure, among others. It should also be evaluated if it balances the risk-benefit, as in the cases of thyroid diseases.
• You Men benefit from a longer fast (such as the 18-hour fast) compared to women, who seem to benefit more from the 14-hour fast. This has to do with the inherent hormonal difference.

And what exactly are the benefits of intermittent fasting?

• hunger control: With fasting we manage to increase sensitivity to our hunger hormones: insulin, ghrelin and leptin. For example: in obesity it is common to have resistance to leptin and therefore the amounts of food consumed are always greater; fasting makes leptin more sensitive and thus lasts longer without wanting to eat.
• Helps control blood sugar levels reduce the risk of type 2 diabetes: fasting increases peripheral sensitivity to the effects of insulin, thus counteracting insulin resistance and reducing the risk of diabetes
• Activates the cellular autophagy process: this will be one of the most important benefits of fasting. According to this natural process, dead, diseased or non-functioning cells are replaced by healthy cells. Almost like the old brown autumn leaves fall off and are replaced by new green leaves. It is therefore a cellular repair process that is activated when we are fasting. The positive implication that it can have in many diseases (especially cancer) is enormous.
• Stimulates the immune system through the autophagy process: fasting, our system is in energy saving mode and, among other things, recycles immune system cells that are not needed, mainly those that are old and damaged. It is also known that when the eating window begins after a fast, the immune system responds by making stronger white blood cells.
• Increased physical and mental energy.which is again associated with periods of fasting where ketone bodies are created, which are another way for our body to obtain energy.
• The 12-hour fast should be observed. by all the adults and the schedules of the routines reconsidered. When the eating window begins, it is important to reduce the carbohydrate load, favoring proteins such as yogurt, eggs and nuts at the first meal.

True or false? Sleep deprivation makes us eat more.

Real. Sleep deprivation alters the production of our hormones that regulate appetite. Ghrelin (hunger hormone) increases and leptin (satiety hormone) decreases, leading to an increased desire to eat and often unconsciously eating high-calorie foods (mainly high in fat).

A frequent question in consultations: since I have compulsive eating, can I do intermittent fasting?

What is described in the literature is that in cases of eating behavior problems, fasting (more than 14 hours) can be risky because there may be a feeling of lack of control due to lack of routines and also because, unconsciously, it is a way of Clearing days out of control. In these cases, the most important thing will be the routine to be defined between the patient and the nutritionist in terms of the number of meals that must be maintained daily, as well as their times.

A podcast suggestion: Learn to eat

In this episode of the podcast that I have on Rádio Observador, I left some advice for those who are afraid of intermittent fasting.

Did you like this newsletter? Have questions about food or want to ask a question you’d like to see clarified in a future issue? Write to me at [email protected].
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mariana chavez She is a clinical nutritionist, author of the podcast Aprender a Comer, on Rádio Observador, and the book Dieta Única (ed. Guerra e Paz, 2016). [ver o perfil completo]????????