This “doctor of the 21st century”, as she defines herself, gives the keys to metabolic flexibility in her new book: physical exercise, rest, good nutrition and stress management

Would you put diesel in a gasoline vehicle? You wouldn’t think of refueling with the wrong fuel, would you? It could have a breakdown. Well, this is how you should treat your body, according to Doctor Isabel Belaustegui Trías (Madrid, October 18, 1975), graduated in Medicine and Surgery from the Autonomous University of Madrid, specialist in Pathological Anatomy and master’s degree in Neural Therapy and Neurofocal Dentistry. In addition to a great informative work, which she has dedicated to the nutritional education platform Vida Potencial, she is a lecturer and writer of titles such as The magic of fasting and now Optimize your metabolism. Recover your metabolic flexibility, improve health and lose weight (Ed. Grijalbo).

“We take more care of our car than the health of our bodyin which we introduce anything,” defends the author. We talked to her about metabolism, that set of chemical reactions that take place in the body’s cells to convert food into energy and help eliminate toxic substances.

“I was phenomenal until I was 30, when my metabolism changed,” we often say lightly about this essential process, but do we understand what triggers its slowdown?
There are two components. The first is the cumulative effect of everything we do throughout life. There comes a time when we cannot continue like this without consequences, because we will have altered metabolic flexibility, which is the ability to generate energy and burn fat well. And the second component, linked to this, that with age we have lower digestive strength. Suddenly, we notice that before we used to binge, but now if we have a binge we feel heavy and we attribute it to the slow metabolism. Maybe we are alleviating it with shots of vinegar or snacks of pickles, without seeing the origin of that previous problem.

One of the great conclusions of his book is to discover to what extent the fact of constantly living on a diet with ups and downs followed by binge eating due to anxiety influences or mistreats the metabolism. What causes this permanent calorie restriction?
Living on a diet or eating many times a day punishes the metabolism. It causes a distortion in the functioning of enzymes and hormones because it involves a permanent activation of insulin every time we eat. Above all, when we eat foods rich in carbohydrates, such as pasta, sugar, the culture of snacks from time to time and several times a day… All this causes us to produce an expulsion of insulin to manage that rise in sugar, glucose in the blood, which is overloading the pancreas, the insulin-producing organ, and the cells that function in that metabolic pathway. They end up saturated and stop functioning correctly: the pancreas begins to enter a state of prediabetes and the cells become deaf to so much noise. This overload of glucose and insulin ends up saturating the metabolic pathways. And the mitochondria, which are those energy plants, are no longer in optimal conditions for everything to go well.
There are people who seem to have a graceful metabolism and nothing makes them fat. How much is genetics and how much is lifestyle that can be modified through our habits?
A lot, because genetics is a part of this equation, but what we know is that epigenetics, what is above genes, that is, the modulation we make of the expression of the manifestation of genetic information, occupies a very important place. It is true that there are people endowed with very useful and enviable wild cards and others who have worse cards, but this gene expression is regulated and modified by the own diet and lifestyle and each can benefit from that.

And what would be convenient to modulate this gene expression?
For example, a diet low in carbohydrates, high in healthy fats and intermittent fasting, which modulates all those insulin spikes.
To what extent is metabolism inherited?
When there is an overload of stress, it has been observed that the expression of genes that have to do with poor management of this stress itself is altered. For example, in the 9/11 attacks it was observed that the children of pregnant women who experienced that traumatic event developed more fears and had learning problems, while the same did not happen in women who had not witnessed something like that. Another experiment in Europe, in the 60s, there was a peak of people who had metabolic syndrome: excess weight, high blood cholesterol levels, hypertension and cardiovascular disease. Looking for what could be behind this, no direct cause was found, but all these people had been born at the same time, that of famine, a great crisis with a lack of food. These pregnant mothers made it easier for the genes with this metabolic syndrome to be expressed in their offspring.
Specific stress is necessary to provoke a reaction to a stimulus, but how does this state of latent stress in which modern society lives affect the metabolism?
It affects us on a very deep level. When we live in permanent stress We have high levels of cortisol and this raises blood glucose because it has a survival purpose: the cells have to have energy to run away. But of course, that sustained over time is a constant increase in glucose that, as we have talked about, leads to prediabetes, diabetes, obesity… Many people with stress gain weight or have a hard time losing weight and the metabolic explanation is this elevation of insulin by cortisol.

On a biological level, what difference is there between the metabolism of a woman and a man, beyond the caloric expenditure of about 500 more kilocalories that they have per day?
There are some basic differences like what you mentioned or, for example, having a tendency to have more or less metabolic flexibility and to accumulate fat in different areas of the body. It has been observed that women generally have a lower resistance to fasting, it costs us more or causes us more stress. And this, from an evolutionary point of view, is explained by that situation in which men were in charge of seeking sustenance and needed to be able to go hunting on an empty stomach and women were in charge of raising and caring for children and They had less activity on an empty stomach. Plus, we change over the years. In childhood, the metabolism of girls and boys is similar and in adolescence, hormonal influence causes women to accumulate more fat in certain areas. During menopause our body also changes due to hormonal changes and we have more difficulty burning fat. We stopped having that guitar silhouette and moved on to that more characteristic shape of the apple man.

Is it true that HIIT training (High Intensity Interval Training or high-intensity interval training) and strength training accelerate metabolism?
Without a doubt, physical exercise has an influence on the metabolism, especially HITT, due to the peaks of intensity, it is very efficient in a short time, and strength, which has a direct association with increasing longevity, that is, fulfilling years with vital functions in full capacity. Two very interesting phenomena occur when we train. We produce testosterone, the growth hormone and the so-called youth hormone, especially when we do multi-joint type training, which involves large muscle groups, such as the squat, the deadlift, the pull, the lunges… Both during , such as in the moments after training and even hours later. And that is metabolic health. Besides, we need muscle to optimize metabolism, and by training we make it grow. It is a great regulator of glucose and insulin, and not only serves to stay strong and protect our bones from possible falls.
Going up and down stairs on foot, getting off one stop early, getting up from your chair to talk on the phone… The so-called NEAT (Non Exercise Activity Thermogenesis or non-exercise activity thermogenesis) also helps metabolism?
It is magical, because it gives us a lot with little effort. The basal metabolic rate can be raised by up to 40% with small gestures that are undervalued. Everything we do that is not necessarily physical exercise, but is a repeated activation over the hours. Even posture affects, because it burns more calories staying upright than sitting limp on the couch. It makes our machinery oiled and it is very interesting because it does not require much effort, providing benefit.

How does the thyroid work in relation to metabolism?
Have a regulatory effect global, including body temperature. The thyroid is a gland that we have in the neck, just like a butterfly. It produces thyroid hormones that act on cells, effectively promoting all metabolic pathways. They influence a multitude of vital functions, for example, intestinal function. Therefore, people with hypothyroidism have a tendency to constipation or a certain amount of confusion, confusion, fatigue, tiredness…

Four keys

How to optimize metabolism without complicating your life

  • Feeding: “Elimination of processed foods to focus on a Mediterranean diet, with foods that are as natural as possible, like our grandmothers did.”
  • Physical exercise: “If you can’t train, at least move as much as possible every day, even in the small gestures of bending down to pick up something that has fallen to the ground. Don’t waste any of those opportunities.”
  • Rest: “Taking care of sleep is key to our health and, of course, metabolic health. Always go to bed at the same time, have dinner at least two hours before going to bed, have low lights at home in the afternoon to calm down. the mind and promote sleep hygiene by eliminating constant screens to promote a calm, silent environment.
  • Stress management: “There is a lot that can be done and that can generate more stress, so the minimum is to take a walk outdoors allowing yourself to receive sunlight, coming down to earth, without mental noise, moving. That is within everyone’s reach.”