The stress our body feels goes beyond a simple unpleasant emotion; it activates the hypothalamic-pituitary-adrenal axis to cause diverse neuroendocrine changes. Chronic stress excessively stimulates the hypothalamic-pituitary-adrenal axis, leading to the continuous secretion of stress hormones such as cortisol. Donguibogam's explanation of essence depletion connects very closely to this state of physical and mental exhaustion caused by chronic cortisol exposure described in modern medicine.
Excessive cortisol can adversely affect the hippocampus, impairing memory and learning capacity. In addition, it disrupts neurotransmitter balance, causing regulation issues with substances such as serotonin, dopamine, and norepinephrine, which manifest as mental fatigue symptoms including depression, anxiety, and impaired concentration. Mental fatigue is not merely from thinking too much, but is the result of chemical changes within the brain.
Furthermore, chronic stress exerts a profound influence on the autonomic nervous system. When the sympathetic nerve remains persistently hyperactive, the heart rate quickens, blood pressure rises, digestive function declines, and muscles tense up. It interferes with sound sleep at night and causes lethargy during the day, unnecessarily draining energy as if the body were constantly preparing to fight or flee. The statement in Donguibogam that the depletion of essence causes vitality to decline and leads to lethargy can be viewed as encompassing this very state of autonomic nervous system imbalance.
The immune system is no exception. Persistently elevated cortisol levels suppress immune cell function, leaving one vulnerable to infection and easily triggering inflammatory responses. Symptoms such as catching colds frequently, minor wounds failing to heal promptly, and worsening allergic reactions correspond directly to the warning in Donguibogam that a lack of essence weakens the body's defenses. Chronic inflammation also serves as a fundamental cause of various chronic diseases.
What about at the cellular level? Chronic stress increases the generation of reactive oxygen species (free radicals), inducing oxidative stress that damages cells. This leads to DNA damage and accelerates cellular senescence, lowering overall bodily function and increasing the risk of chronic disease. The classical metaphor that the depletion of essence makes the body dry and age rapidly connects directly with the modern scientific theory of cellular senescence. Hypofunction of the mitochondria, which are responsible for cellular energy metabolism, is also closely related to chronic fatigue.
In conclusion, the classical concept of essence can be understood to represent a comprehensive state of vital energy depletion encompassing the stress response system, neurotransmitter changes, autonomic nervous system imbalance, immune hypofunction, and even cellular oxidative stress and inflammatory reactions described by modern medicine. Our bodies and minds are far more organically connected than we might think, and stress is not merely a matter of mood, but a serious factor that threatens the fundamental vitality of our body. Protecting our body's precious essence lies in the exact same context as stress management, which is regarded as paramount in modern medicine as well.
