When a father or mother murders her children, we try to find an explanation for this dramatic situation. Meanwhile, this behavior also happens among animals. The factor that causes the female to bite or abandon her young is external stress. Fear of losing a job, crazy pace of everyday life and unpredictable stress make us suffer from mental disorders more and more often. Chronic depression and schizophrenia can have dire consequences.
Recent research suggests that most diseases are probably rooted in stress. The list of stress-induced health conditions is long. Diseases of the heart and circulatory system constitute the largest group. More and more research results also indicate that stressed people are more likely to develop certain types of cancer. Stress also often triggers or exacerbates the symptoms of autoimmune diseases, such as Hashimoto’s, Graves’, rheumatoid arthritis (RA), type 1 diabetes, dry mucosa syndrome, and ulcerative colitis.
There are many indications that stress may play a role in the development of mental disorders. In addition to the large number of neuroses caused by stress, it is believed that stress contributes to the pathogenesis of mental illnesses such as depression or schizophrenia. Stress is a very complex phenomenon and its strict definition is extremely difficult. In everyday life, the term is often used to describe nervousness or anxiety, and often the factor that causes these conditions. The term stress comes from physics and refers to the different types of stresses, pressures or forces that act on a particular system. The concept of stress in biology was introduced by Hans Hugh Selye, a Canadian endocrinologist of Austrian origin. According to Selye, stress is a dynamic adaptive reaction of the organism resulting from the difference between the possibilities and the requirements of the situation, prompting to undertake remedial actions that are to restore the state of balance, i.e. homeostasis. Homeostasis is the normal state of all living things. Homois – even, similar; stasis – duration (from Greek), i.e. homeostasis means the stability, balance of the internal environment of the organism. If this balance is maintained, the body is healthy and more resistant to all diseases.
In medical terminology, stress is a disruption of homeostasis caused by a physical or psychological factor. Stress in understanding the body’s reaction to unfavorable external factors is our evolutionary heritage. In the distant past, a person’s reaction to stress most often required a fight or flight, i.e. very intense, brief activity. Despite the passage of thousands of years of evolution, to this day, the first reaction to a stress factor is stimulation of a part of the nervous system called the sympathetic nervous system.
As a result, within a few seconds, a very strong secretion of two hormones by the adrenal glands occurs: adrenaline and norepinephrine. This leads to an acceleration of the heart rate, breathing, pupil dilation – that is, it prepares the body to fight or flee, increasing metabolism and sharpening perception. If the stressful situation lasts longer or the stress factor is very strong, another biological system is activated, i.e. the hypothalamic-pituitary-adrenal axis. The hypothalamus secretes the hormone corticoliberin (CRH), which stimulates the pituitary gland to secrete the hormone corticotropin (ACTH). ACTH, in turn, stimulates the adrenal cortex to secrete mineralocorticoids and glucocorticoids, of which cortisol is the most abundant in humans. Cortisol is the most active of all glucocorticoids and plays a decisive role in regulating metabolic processes during stress. By inhibiting the use of metabolic substances and at the same time promoting their formation, cortisol delivers glucose, amino acids, and fatty acids to the bloodstream. It also suppresses immune and inflammatory functions. The release of cortisol into the circulation guarantees the maintenance of an appropriate level of adenosine triphosphate (ATP – the “energy fuel” of cells) in the body. As a result of increased metabolism of glucose, fatty acids and amino acids, cortisol adjusts the production of ATP to the increased needs of the body. In summary, the hormones released from the adrenal glands prepare the body for immediate action, while cortisol is responsible for the mobilization of energy (glucose) and other substances necessary to maintain this action.
The above definition of stress and the processes taking place in the body during stressful situations clearly shows its positive aspects as a process that facilitates survival. Paradoxically, on the one hand, stress as an organism’s response to a threat is an undoubted evolutionary gain, and on the other hand, stress is associated with a huge number of diseases. Where does this contradiction come from? As already mentioned in the primitive man, the stress response was a fight or flight, a brief, intense activity followed by a relaxation period until the next threat. We can observe similar situations in wild animals. Over the course of thousands of years, in the progress of civilization, man has created communities living in conditions that deviate more and more from the original way of life. Recent decades have brought an avalanche of changes in our lifestyle and have almost completely isolated us from nature. Modern life requires a completely different adaptation, however, the transformation of the surrounding environment and our lifestyle has happened too quickly for the appropriate evolutionary mechanisms to work. Our body and its neurohormonal mechanisms have remained unchanged and react to threats as they did thousands of years ago. This is where the problem lies.
It should be noted that not all stress is harmful. The author of the concept of stress, Hans Selye, mentioned above, distinguished between constructive and destructive stress. He believed that stress can play a positive role because in certain situations it mobilizes a person to act more effectively. He called such positive stress eustress, and excessive stress causing damage was called distress. Modern research confirms that in moderate doses, stress motivates to work, stimulates action and is a driving force. Moderate stress increases the ability to cope with the adaptation requirements of the environment, thanks to which it enables mental development. Many researchers of the phenomenon define it as the basic factor of development. Stress in the right dose is the driving force behind action. Only too strong or prolonged stress brings about an adverse effect. Stress that occurs too often and lasts too long can lead to serious disturbances in the functioning of the entire body. Already in the 50s, Selye hypothesized that a number of somatic diseases are the result of a person’s inability to cope with stress. This phenomenon is called the so-called failure. general adaptation syndrome and described it in his book The Stress of Life.
The main culprit and source of stress-related illnesses is chronic stress. To explain its mechanism of action, it is necessary to explain the concept of allostasis, introduced by one of the leading scientists in the study of the mechanisms of stress, Bruce McEwan. According to him, the body, in response to strong environmental changes, reduces or increases its vital functions in order to establish a new state of equilibrium. The ability to maintain a state of equilibrium by making multi-system changes McEwen calls allostasis (Greek from stability through change). Allostasis actively maintains the constancy of the internal environment. It is a condition in which the body survives, but suffers adverse effects. Under normal conditions, allostasis should maintain a state of equilibrium until the organism adapts to a new life situation or the environmental change ceases. Maintaining allostasis beyond what is necessary until it begins to do more harm than good McEwen calls allostatic stress. The allostatic load sustained for a long time is extremely unfavorable and leads to the death of the body.
Accelerated civilization development and rapid political transformations created uncertainty the next day, thus depriving us of a foreseeable future on which to base our plans. As a result, our body is constantly mobilized and ready to fight. Unfortunately, today we are unable to avoid or eliminate many, if not most, stress factors affecting us. The inability to effectively fight or escape from unfavorable stimuli is another factor that mobilizes the body to an even greater extent to solve the threat. This leads to a vicious cycle in which the stress mechanism is a self-winding death spring. The ever stronger mobilization of the organism becomes useless, even harmful and devastating for the human body and mind. Long-term elevated levels of stress-related hormones result in sustained high blood pressure, excess glucose levels, and increased metabolism. This physiological state, if normal within seconds or minutes, is a very strong pathology in the long run, and consequently leads to pathophysiological processes and anatomical degenerations in the body. According to McEwen’s theory, this is a long-term allostatic load. The question, however, is: if we can neither avoid stressors nor effectively eliminate them, why don’t we get used to them? It is known from animal experiments that repeated stress stimuli, initially causing severe stress, after prolonged, repeated use, provoke an increasingly weaker response. Allostasis occurs for a short time, after which the animal adapts to chronic stressors, which prevents the unfavorable phenomena of long-term allostatic stress. Unfortunately, this described mechanism of adaptation occurs only in the situation of applying multiple, identical stress stimuli. If the animal is subjected to multiple stress stimuli of a different and unpredictable nature (e.g. disturbance of the circadian rhythm, tilting the cage, soaking the lair), adaptation does not occur. This type of pattern of mild, but unpredictable and diverse stress factors is used to induce in experimental animals, e.g. rats, a state that is one of the best animal models of depression. In Poland, it is successfully used in the laboratory of prof. Mariusz Papp at the Institute of Pharmacology of the Polish Academy of Sciences in Krakow. The results of animal studies presented above show that the killing effect of chronic stress on humans is caused not so much by the strength of stressful events, but by their unpredictability and diversity. Indeed, in the world around us, the variability of the external environment and the avalanche of information about surprising and varied threats, arriving without any interruption from the media, is unprecedented in the history of mankind. As a result, for months or even years we live or rather feel that we live in a situation of constant threat to our lives. As a consequence, the body, as already mentioned, leads to a state of chronic elevation of stress-accompanying hormones. High, long-term elevated cortisol levels are believed to be one of the causes of disturbances in the control of the hypothalamic-pituitary-adrenal axis – a system that is crucial for the regulation of physiological functions such as sleep, appetite, emotional responses, and the body’s resistance to infections. At the same time, the elevated level of cortisol has a destructive effect on the neuroanatomy (thus impairing their function) of the hippocampus and the amygdala complex – structures responsible for the formation of memory and emotional reactions.
A classic example of the development of depression under the influence of multiple stress is the story of Teresa B. widely commented in the media. This woman was subjected to numerous unpredictable stress stimuli for a long time. She suffered physical aggression from her partner, lost her job, lost her apartment, and found herself in financial trouble. These numerous negative events probably caused the first symptoms of depression to appear. Despite her treatment, another negative stimulus – appointing a probation officer for her two younger children – caused an acute depressive attack, as a result of which she poisoned her children with antipsychotic drugs and attempted suicide herself.
The question is; if the current civilization causes us constant unpredictable stress, leading to many somatic diseases and mental disorders, why are there still healthy people? Perhaps this amazing fact that healthy individuals exist in the present world is only a matter of a short time. The disease of the 2000st century is defined as depression, in XNUMX in the United States, coronary artery disease was the most common cause of death, we observe a sharp increase in the incidence of various types of cancer (breast, prostate, pancreas, lung, brain, testes, lymph glands), peptic ulcer disease and impotence is inseparable from professional success, neurosis has become as common as a cold, and statistics tell us that the situation will worsen in the coming years.
The rapidly growing number of addictions to various stimulants, intoxicants or other psychoactive substances (designer drugs) in recent years results mainly from the desire to reduce stress to a minimum, improve mood and detach from tiring reality. As a consequence, it leads to an increase in the wave of diseases caused by the constant use of harmful substances and contributes to an increase in the frequency of diseases indirectly caused by stress. Fortunately, there are also methods that are harmless to your health to free yourself from the negative effects of stress. Doing what you like helps relieve stress. It can be a physical activity, a favorite reading. Condition: this activity must focus all our attention. It is important to develop your hobbies and do what we enjoy. Stress must not accumulate. An honest conversation with your friend and sharing your worries with him will help you relax. Listening to classical music or recorded sounds of nature is effective. Yoga and meditation are gaining more and more popularity. By combining elements of physical, breathing and mental exercises (contemplation), they reduce stress and thus contribute to the improvement of psychophysical health. There are also professional relaxation techniques that are used under the supervision of psychotherapists. The pharmaceutical industry has also recently been flooding us with pharmaceuticals and dietary supplements, which are supposed to quickly eliminate the negative effects of stress. Is that enough? Will this allow us to control harmful stress and survive as a species in the hostile world we have created? We will certainly find out about it soon …
Read more about stress at work!
Literatura:
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