What is H. pylori?

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    Last Updated: May 16, 2025

    Helicobacter pylori (H. pylori) is a pathogenic bacterium that colonizes the human stomach; it affects approximately 50% of adults globally. Although it is often asymptomatic, H. pylori infection is associated with an increased risk of gastric cancer.

    Helicobacter pylori (H. pylori) is a pathogenic bacterum that colonizes the human stomach. Around 50% of adults worldwide are infected with H. pylori, but not every infection causes symptoms. However, compared to uninfected individuals, those with an infection are three to six times more likely to develop gastric cancer. [1]

    H. pylori is capable of reducing stomach acid, which leads to gastric microbial overgrowth and higher proportions of other potentially pathogenic microbes. It can also cause the formation of biofilm—a structured collection of microbes suspended in a protective matrix—which promotes abnormal bacterial colonization in the stomach.[2]