The sunlight we encounter daily, especially ultraviolet radiation, acts like a double-edged sword for skin health. While essential for vitamin D synthesis, excessive exposure becomes the primary driver of skin aging. Modern medicine has detailed how ultraviolet radiation affects skin cells. Ultraviolet A penetrates deep into the dermis, breaking down and altering collagen and elastin fibers, while ultraviolet B mainly damages the epidermis, causing sunburn and DNA damage.
The concept of body fluids in the Donguibogam aligns closely with extracellular matrix health, fluid balance, and the antioxidant defense system. Structural components such as collagen, elastin, and hyaluronic acid densely fill the dermis, functioning much like the traditional concept of body fluids. Having sufficient body fluids means skin cells retain enough moisture to remain firm and elastic, supporting the defenses that protect against external irritation.
Ultraviolet radiation sharply increases the production of reactive oxygen species (free radicals) within skin cells. These reactive oxygen species damage cell membranes, break down DNA, and accelerate the activity of matrix metalloproteinases, enzymes that degrade collagen and elastin. As a result, essential structural substances are depleted and skin barrier function weakens, accelerating moisture loss. Ultimately, the skin undergoes photoaging: it dries out, loses elasticity, develops deeper wrinkles, and experiences increased melanin production that manifests as hyperpigmentation such as melasma and blemishes.
Furthermore, fluid deficiency affects the skin's immune response and exacerbates inflammation, which can further stimulate hyperpigmentation. When body fluids in the skin are sufficient, intercellular communication proceeds normally, damaged tissue recovers steadily, and an active antioxidant system works to neutralize attacks by ultraviolet-induced reactive oxygen species. Modern medicine supports this perspective from the Donguibogam: properly managing the body's internal moisture and nutritional state—its body fluids—serves as the primary defense for protecting the skin from external damage and maintaining its health. Beyond applying sunscreen, supporting health from within the skin is essential.
