In modern medical terms, the concept of upright qi in Donguibogam corresponds closely to the immune system. The immune system forms an intricate defense network guarding against external pathogens such as viruses and bacteria. It divides broadly into innate immunity and acquired immunity. Innate immunity provides immediate, non-specific protection through the skin, mucosa, natural killer cells, and macrophages. Acquired immunity utilizes B cells and T cells that develop targeted responses based on memory of specific pathogenic bacteria. Falling ill with every seasonal transition reflects an imbalance and functional decline in these defenses.
Modern daily life contains multiple factors that impair immunity. Chronic stress leads the adrenal cortex to oversecrete the stress hormone cortisol. Excess cortisol dampens inflammatory responses while lowering the activity of immune cells, particularly inhibiting T cell development and function, which weakens resistance to viral and bacterial infections. Sleep deprivation similarly undermines immune regulation. During sleep, the body restores immune cells and secretes the immunomodulator cytokine. Insufficient rest interrupts this recovery process, increasing susceptibility to infection.
Gut health also plays a central role, as dysbiosis directly alters intestinal mucosal immunity, which houses more than 70 percent of the immune system. An overgrowth of harmful bacteria accompanied by mucosal irritation triggers inflammation, contributing to decreased systemic immunity. Inadequate intake of essential nutrients such as vitamin D, zinc, and selenium further impairs normal immune cell operation. In addition, sustained sympathetic nerve activation suppresses immune cell circulation and performance, whereas parasympathetic nerve tone supports immune activity. Chronic lifestyle stress maintains heightened sympathetic activity, disrupting overall balance. Together, these elements weaken immune defenses, presenting as recurrent colds, allergies, and chronic fatigue. Catching infections frequently indicates that internal resistance is unprepared. Supporting the immune system therefore requires an approach that addresses the broader physical environment rather than relying only on temporary medication.
