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How does Helicobacter pylori infection damage the stomach?
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digestive system disease
Learn why eating large meals can cause bloating, heartburn, and discomfort.
Helicobacter pylori damages the stomach by compromising the protective mucosal lining, which normally shields the organ from the corrosive effects of gastric acid and digestive enzymes.12
Although the stomach is a highly acidic environment, H. pylori survives by converting urea—a waste product present in the stomach—into carbon dioxide and ammonia. This chemical conversion creates a more neutral local environment for the bacteria. While the exact mechanism is not fully understood, this process leads to the breakdown of the mucosal lining. Once the lining is weakened, it can no longer resist the acidic effects of gastric juice, which can result in the formation of an ulcer.12