The wisdom of the Donguibogam aligns remarkably well with modern science. The adverse effects of cold water on the stomach during meals go beyond a mere sensation of feeling cold inside; they involve physiological mechanisms that disrupt our complex digestive system.
First, the stomach must maintain an optimal temperature of around 37ยฐC to digest food. At this temperature, various digestive enzymes in gastric juice, including the protease pepsin, function actively. When cold water enters, the internal temperature of the stomach drops sharply, significantly reducing the activity of digestive enzymes. Just as our muscles stiffen and movement slows down in cold weather, digestive enzymes cannot perform their roles properly. As a result, the breakdown rate of food slows noticeably, leading to dyspepsia.
In addition, cold water negatively affects gastrointestinal motility. Our stomach mixes food with digestive fluids and sends it down to the small intestine through peristalsis, but sudden cold qi can disrupt the rhythm of contraction and relaxation in the stomach wall muscles. In particular, the vagus nerve is an essential autonomic nerve that regulates the motility and secretion of the digestive organs, and cold stimulation can inhibit vagus nerve activity, slowing gastrointestinal motility. This leads to delayed gastric emptying, causing bloating, stuffiness, and persistent heavy discomfort in the epigastrium. Over time, it can worsen into chronic dyspepsia or functional dyspepsia.
Furthermore, the reduction of blood flow volume in the gastrointestinal mucosa presents another problem. When cold water enters the stomach, the blood vessels around the gastric mucosa constrict, which can reduce blood supply. The digestive organs require an abundant blood supply to break down food and absorb nutrients, but reduced blood flow volume weakens the protective capacity of the stomach wall and can slow the recovery of damaged gastric mucosa. This may raise the risk of developing gastrointestinal diseases such as gastritis and gastric ulcers, or worsen existing conditions. A simple glass of cold water can burden the stomach significantly. Protecting your stomach with warmth helps restore healthy digestion.
