When your stomach hurts after eating cold food, what happens from the perspective of modern medicine? Beyond the stomach simply becoming cold, this can be seen as a phenomenon where the intricate systems of our body react in combination. First, when cold food or drinks enter the stomach, blood vessels in the gastrointestinal tract constrict. It is just like skin turning pale when you dip your hands in cold water. When blood vessels constrict, blood supply to the stomach temporarily decreases, which affects the secretion of digestive enzymes and gastrointestinal motility, thereby lowering digestive capacity. Because of this, food stays in the stomach longer, and improperly broken-down food generates gas or causes pain in the intestines.
In this process, our body's autonomic nervous system plays an important role. The autonomic nervous system is divided into sympathetic nerves and parasympathetic nerves, and cold stimuli tend to particularly activate the sympathetic nerve. When sympathetic nerve activity is elevated, motility of the gastrointestinal tract decreases, and blood may be redistributed to areas other than the stomach, such as muscles. Conversely, parasympathetic nerves promote digestive function; when sympathetic nerves become excessively active, this balance is disrupted, which can worsen dyspepsia symptoms.
How, then, can acupressure on LI4 described in Donguibogam be explained from this modern medical viewpoint? LI4 is an acupoint belonging to the large intestine meridian; neurologically, acupressure on this area stimulates specific nerve pathways to send signals to the brain. These signals affect autonomic nervous system regulatory centers such as the brainstem and hypothalamus, helping to suppress excessively activated sympathetic nerve activity and activate the parasympathetic nerve. In other words, acupressure on LI4 can contribute to relaxing a tensed gastrointestinal tract, improving blood circulation, and promoting the secretion of digestive enzymes.
In addition, acupressure on LI4 can promote the secretion of endogenous opioids such as endorphins, bringing about a pain-relieving effect. It works on a similar principle to how we unconsciously rub an area when it hurts. Furthermore, the physical stimulation delivered through LI4 acupressure can be expected to inhibit pain signals in the brain according to the gate control theory. On the pathway where pain signals originating from the stomach travel to the brain, other sensory signals from the stimulation of LI4 are transmitted to the brain ahead of the pain signals, resulting in feeling less pain.
In conclusion, rather than being a mere act of rubbing the hand, acupressure on LI4 has scientific mechanisms that regulate gastrointestinal tract function and relieve pain through neurological and endocrinological pathways. When stomach function declines and pain occurs due to cold qi, acupressure on LI4 is a wise method that supports the body's natural recovery capacity, restores autonomic nervous system balance, and induces a warm, comfortable digestive state.
