Modern science also offers interesting research findings that support the wisdom of Donguibogam. The kidney described in Donguibogam can be understood not merely as an organ that produces urine, but as a concept encompassing the modern adrenal gland and the hypothalamic-pituitary-adrenal axis. Stress stimulates this hypothalamic-pituitary-adrenal axis, promoting the secretion of stress hormones such as cortisol. When cortisol remains chronically elevated, it adversely affects the hair growth cycle.
In particular, it suppresses the growth of anagen phase hair follicle cells and causes a rapid transition to the telogen phase, which can trigger telogen effluvium, where large amounts of hair fall out at once. Severe stress also disrupts the immune system, increasing the risk of autoimmune diseases such as alopecia areata, where the body attacks its own hair follicles. Additionally, cortisol is known to inhibit melanin production, thereby promoting the appearance of premature gray hair.
The passage stating that hair is the surplus of blood from Donguibogam is interpreted in modern medicine as the importance of blood circulation and nutrient supply. Stress hyperactivates sympathetic nerves, constricting scalp microvessels and hindering blood circulation. This impedes the delivery of oxygen and nutrients to hair follicles, slowing or weakening hair growth. When essential nutrients for hair growth, such as iron, protein, and vitamin B complex, become deficient, hair easily becomes brittle and prone to falling out. In particular, chronic stress can also affect gut health, impairing nutrient absorption and consequently negatively impacting hair health.
Ultimately, stress exerts a detrimental impact on hair health from multiple angles, including hormonal balance, the immune system, blood circulation, and nutrient absorption. This is why, rather than relying solely on anti-hair loss shampoos or nutritional supplements, fundamental care is needed to nurture the kidneys as our body's roots and blood as our nourishment.
