H. Pylori and SIBO: Low Stomach Acid, Gastritis & Hypochlorhydria How H. pylori can lower stomach acid and is linked to SIBO and methane overgrowth, how each is tested, and whether treating H. pylori clears SIBO. Sep 20, 2026 5 min read #h-pylori #stomach-acid #hypochlorhydria #root-causes #gastritis