What If Your Scalp and Face Are Chronically Red and Itchy? Seborrheic Dermatitis: An Issue of Genetics Deep Within the Skin?

From the perspective of modern medicine, seborrheic dermatitis is a chronic inflammatory skin disease that mainly occurs in areas with active sebaceous gland activity, namely the scalp, face, and chest. Along with epidermal barrier dysfunction, the overproliferation of Malassezia yeast is considered one of the primary causes. Malassezia is actually a microorganism that normally resides on our skin, but when sebum secretion increases or immunity weakens, it falls out of control and triggers an inflammatory immune response. Here, 'heat' in Korean medicine can be linked to excessive sebum secretion and inflammatory reactions—that is, an overheated state of the skin—while 'dampness' can be interpreted through symptoms such as excess sebum, keratin, and exudate. According to modern research, the gut-brain-skin axis connection between gut health and skin health also exerts a significant influence on seborrheic dermatitis. Gut dysbiosis triggers systemic inflammation, which in turn influences skin immune responses and can worsen seborrheic dermatitis. In addition, stress disrupts our body's autonomic nervous system and endocrine system, increasing the secretion of cortisol, which stimulates the sebaceous gland and accelerates inflammatory reactions. Stress-induced heat, expressed in Korean medicine as 'liver fire' or 'heart fire', can be seen as sharing the same context with neuroendocrinology in modern medicine. Ultimately, seborrheic dermatitis is not just a surface skin problem, but a signal produced by the combined interactions of imbalances in our body's complex systems—namely immunity, hormones, nerves, and the microbial environment. Although genetic predisposition is also an important factor, genes are expressed by the environment, so it can be managed sufficiently through lifestyle improvements.