What is Allostasis?
Allostasis is the name given to the mechanisms that guarantee the physiological stability of a living organism
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The concept of “allostasis” was conceived by Peter Sterling, physician and physiologist, and by Joseph Eyer, neurologist, in 1988. Allostasis characterizes the mechanisms and tools that guarantee the establishment and maintenance of homeostasis. The amount of metabolic energy required for a given physiological mechanism to maintain physiological balance is called the allostatic load. Decompensation of homeostasis due to allostatic overload in some of the body's defense tools can damage health.
Homeostasis is guaranteed by certain physiological processes, which occur in organisms in a coordinated manner. The mechanisms that control body temperature, pH, volume of body fluids, blood pressure, heart rate and concentration of elements in the blood are the main allostatic tools used to control physiological balance. In general, these mechanisms work through negative feedback, which acts to reduce a given stimulus, ensuring the proper balance for the body.
Allostatic charge
The amount of metabolic energy necessary for a given physiological mechanism to maintain homeostasis is called the allostatic charge. The decompensation of homeostasis due to allostatic overload in some of the body's defense tools can cause several damages to health. In other words, when the body expends more energy than it should to reverse the stimulus that disrupted its balance, an allostatic overload occurs, which increases the risk of disease.
A physiological response always occurs in response to a stimulus that disrupts homeostasis. Thus, an action on the individual, whether psychological or physical, will have as a response the deviation of homeostasis and a consequent allostatic reaction to regain balance. Stress is an example of a common stimulus in people's daily lives and corresponds to a real or imaginary event that threatens homeostasis, requiring an allostatic response from the body.
Expectations of response to a stimulus can be positive, negative or neutral. When the answers are positive and end a cycle of aggression, returning to homeostasis, the individual's health is not put at risk. On the contrary, when the allostatic charge is maintained for long periods or the adaptive response that would end the cycle of aggression does not occur, we have allostatic overload and the consequent damage to health.
This damage can manifest itself in several ways, against the background of tissue loss (degeneration), hypersensitivity, functional overload (hypertension) or psychological disorders (anxiety, depression). Daily stresses can be related to the onset or worsening of symptoms caused by this damage.
Conclusion
Keeping the internal environment in balance is essential for the proper functioning of the systems that make up the body of any living being. Enzymes, for example, are substances that act as biological catalysts, accelerating the speed of various reactions. To perform their function, they need a suitable environment, with temperature and pH within a normal range. Therefore, a balanced body is a healthy body.
