Modern medicine defines gastroesophageal reflux disease as a condition where stomach contents flow backward into the esophagus, causing inflammation. Hypofunction of the lower esophageal sphincter, which normally prevents this acid reflux, is considered a primary cause. When this sphincter becomes lax, gastric acid easily flows into the esophagus, and the near-neutral esophagus suffers damage from exposure to strong gastric acid, unlike the stomach which is designed for an acidic environment.
However, it is not merely a sphincter problem. Our digestive process is regulated by a complex nervous system, especially the autonomic nervous system. Under stress, the sympathetic nerve is activated while the parasympathetic nerve is suppressed, which can impair overall digestive function. Gastric acid secretion may become excessive, or decreased gastrointestinal motility may cause food to linger longer, directly leading to abdominal distension. This decreased gastrointestinal motility and acid reflux are closely linked, often with autonomic nervous system imbalance at their center.
Recent studies highlight the importance of the gut-brain axis. Our gut health profoundly affects brain function and mental well-being, while stress perceived by the brain directly impacts the gut. Chronic stress alters the gut microbiota environment, creating conditions where harmful bacteria can easily proliferate, which can further aggravate indigestion and abdominal distension. Furthermore, conditions such as irritable bowel syndrome or small intestinal bacterial overgrowth frequently co-occur with reflux esophagitis, which likewise often stems from an imbalance in the intestinal environment.
Dietary habits are also crucial. Overeating, late-night snacking, greasy, spicy, or salty irritating foods, and carbonated beverages can promote gastric acid secretion and weaken the sphincter, triggering or worsening reflux symptoms. In addition, these foods generate intestinal gas, intensifying abdominal distension. We must remember that reflux esophagitis and abdominal distension are not isolated stomach problems, but complex symptoms involving our digestive system, nervous system, and even our stress management abilities. Beyond simple symptom relief, an effort to restore overall bodily balance is essential.
