Let us examine this Donguibogam concept of essence through modern medicine. The phenomenon of the body turning cold from an essence deficiency aligns with the clinical presentation of cold hypersensitivity of hands and feet. This condition often stems not from external cold alone, but from dysfunction in the thermoregulation system. Blood carries warmth throughout the body, so if blood circulation is impaired for any reason, warm blood cannot reach the tips of the hands and feet properly, leading to chilliness.
At the center of thermoregulation is the autonomic nervous system. Divided into sympathetic and parasympathetic nerves, it automatically coordinates functions essential for life, including vasoconstriction, vasodilation, heartbeat, and digestion. When autonomic nervous system balance is disrupted by stress, overwork, or irregular habits, sympathetic nerve activity can become excessively elevated. When the sympathetic nerve is stimulated, vasoconstriction occurs, blood flow volume to the hands and feet drops, and the extremities become cold. In Korean medicine, the depletion of essence is conceptually very similar to this loss of physiological balance.
For women, hormonal changes are another key factor. Estrogen helps dilate blood vessels. During periods of rapid hormonal fluctuation, such as across the menstrual cycle, pregnancy, childbirth, or menopause, unstable estrogen secretion can cause frequent vasoconstriction and worsen cold extremities. Endocrine dysfunction such as hypothyroidism can also lower the metabolic rate, reducing overall body temperature and chilling the hands and feet. Just as Donguibogam described essence as the 'beginning of yin and yang,' modern medicine identifies hormones and the autonomic nervous system as systems that regulate delicate bodily balance.
If cold extremities worsen in certain postures or come with color changes, turning white, then blue, and then red, one should consider vascular disease such as Raynaud's phenomenon. Cold hypersensitivity of hands and feet is more than mild discomfort; it can be an important physiological signal. Think of deep essence depletion as presenting today through these complex physiological and pathological mechanisms. Rather than simply warming the hands and feet externally, one needs to restore overall bodily balance and replenish root energy.
