Why does prolonged use of proton pump inhibitors (PPIs) that reduce stomach acid secretion increase the risk of small intestinal bacterial overgrowth (SIBO)?

💡 Explanation

The risk of SIBO increases because PPIs elevate the stomach's pH, weakening the gastric acid barrier's antimicrobial effect; therefore, bacteria from the colon can translocate to the small intestine more easily, rather than being destroyed in the stomach's acidic environment.

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