Modern medicine diagnoses symptoms similar to cholera morbus described in Donguibogam as acute gastroenteritis or travelers' diarrhea. These symptoms usually occur when various microorganisms such as bacteria, viruses, and parasites infiltrate our digestive system. Especially when traveling, the probability of exposure to new types of microorganisms that one does not normally encounter increases significantly. The external pathogen discussed in Donguibogam can be understood as the pathogenic microorganism of modern medicine.
When our body recognizes these foreign invaders, it immediately assumes a defensive posture. The mucosal cells of the small intestine and large intestine promote the secretion of water and electrolytes to expel invading bacteria and toxins, and drastically increase intestinal peristalsis. At this time, our body activates the parasympathetic nerve within the autonomic nervous system to make intestinal motility even more active. In this process, the stomach rumbles, loose watery diarrhea occurs frequently, and in severe cases, it is accompanied by vomiting. It is just like all troops moving in unison on a battlefield to drive out the enemy quickly. This is a very natural immune response through which our body attempts to protect itself.
Furthermore, Donguibogam's perspective emphasizing the harmony of qi connects remarkably well with the gut-brain axis theory from a modern neuroendocrinological perspective. Jet lag while traveling, fatigue, tension from an unfamiliar environment, and anticipation and anxiety regarding new food can all act as stress on our brain. The brain secretes stress hormones such as cortisol, which directly affect intestinal motility and intestinal permeability. When intestinal permeability increases, harmful bacteria or toxins can easily penetrate into the bloodstream, which in turn excessively stimulates the immune response, causing diarrhea or worsening symptoms. This is why those with an inherently sensitive gut or vulnerability to stress experience reactions to local water more easily while traveling.
In addition, the balance of the microbial ecosystem in the gut, that is, the gut microbiome, is also very important. A normally healthy gut maintains balance as diverse beneficial bacteria suppress the proliferation of harmful bacteria. However, consuming unfamiliar food or having irregular eating habits during travel easily disrupts this microbial balance. When harmful bacteria become dominant, they cause an inflammatory response, damage the intestinal mucosa, reduce digestive and absorptive functions, and induce diarrhea. The expression in Donguibogam stating when the qi within the body loses harmony can be seen as an astute observation of this very imbalance in the gut microbiome.
In conclusion, travelers' diarrhea goes beyond a simple upset stomach; it is a comprehensive phenomenon in which our body's complex defense system, the gut-brain axis, and the gut microbiota environment respond to external changes. Because all these factors operate organically to sound an alarm in our body, when symptoms appear, listening to the signals sent by your body and providing adequate rest and care is more important than anything else.
