The expression “having a slow or fast metabolism” is widespread in society, but can the metabolism speed up or slow down? do we know what metabolism is?
Metabolism is something that many people have heard mentioned at some time, but do not always know how to define exactly. Generally, the concept is associated with the figure. However, it goes far beyond that. In reality, metabolism has to do not only with how thin or not we are, but with the way we take advantage of food to be healthy and help the body to perform its functions properly.
In this article we explain some basic concepts about metabolism so that we can get right into the explanation of whether metabolism is something that can be activated, accelerated or slowed down.
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What is metabolism?
Metabolism, if we take as a reference the etymology of the word in Greek, refers to the quality that organisms have of changing the chemical nature of certain substances. Thus, if we specify a little more, metabolism would be the set of chemical processes that take place in our body. All these processes are the basis of life on a molecular scale and allow us as living beings to grow, reproduce, maintain our structures and respond and adapt to various stimuli.
However, when we talk about metabolism we tend to be more familiar with numbers such as the calories our body expends by living or doing activities or the energy we consume through food. From here we can extract three concepts that will help us to better understand the concept of metabolism, at least at a colloquial level. We speak of basal metabolic rate, thermic effect of food and NEAT or caloric expenditure not associated with exercise.
What is basal metabolic rate?
The basal metabolic rate is nothing more than the energy that our body expends just by the fact of living, even if we were lying 24 hours in bed. It can account for up to 70% of a person’s daily caloric expenditure.
When people talk about fast or slow metabolisms they are referring to this basal rate which is mostly determined by fat-free mass, i.e. basically muscle mass, water and organs. Although the brain and visceral organs account for only 12% of fat-free mass, they consume much more energy than muscle mass.
Having a higher or lower basal rate is not a good indicator of body weight since people who expend more often eat more and vice versa.
Finally, if a person has a higher or lower basal energy expenditure that cannot be explained by the above, it is usually due to a previous pathology that should be addressed by a physician.
What is the thermic effect of food?
Simply put, the thermic effect of food is nothing more than the energy that our body invests in digesting, absorbing and metabolizing the food and nutrients that we ingest. In other words, part of the energy we consume through food is “lost” in the process of digestion and various metabolic processes.
Dietetic and nutrition professionals usually standardize this energy consumption at around 10% of a person’s total energy expenditure.
What is NEAT?
In terms of the physical activity that we do and that involves energy expenditure, we can divide it into those that have to do directly with physical exercise, such as going for a run or training at the gym, and those that are not associated with it, such as walking to do the shopping or doing the housework, the Non-Exercise Activity Thermogenesis.
It is very important to take NEAT into account especially when we want to lose fat because it is an expenditure that is practically effortless and depends solely on us, on how active we are willing to be.
Can we speed up the metabolism?
Colloquially speaking, yes, physiologically speaking no, since for something to go fast it has to be associated with a speed or duration and metabolism is not the case.
Colloquially we understand as accelerating the metabolism the fact that we spend more calories or lose fat faster. In this sense, the only thing that can have an impact is exercising on the one hand and having a high NEAT on the other.
Manipulating our basal metabolism is not possible (unless we suddenly gain 30 kilos of muscle mass) and the thermic effect of food cannot be manipulated either, or at least not significantly.