The reflux of stomach contents is caused by the lower esophageal sphincter relaxing or being subjected to abnormally high pressure, which could be due to delayed stomach emptying, a hiatal hernia (one in which the stomach bulges through the diaphragm into the chest cavity), or visceral hypersensitivity (excessive signaling from the nerves of internal organs).[1] Contrary to popular belief, H. pylori isn’t a confirmed cause of GERD, and its treatment has been linked to improvements, worsening, or no effect on GERD symptoms.[2][3] Current evidence has not been able to point to stomach acidity alone as a cause of GERD, and it’s likely that multiple factors contribute to the condition.[4][5][6]
Risk factors for GERD include being 50 years or older, smoking, frequently using non-steroidal anti-inflammatory (NSAID) drugs or aspirin, having obesity, living at a low socioeconomic status, and drinking alcohol.[1][7] Sleep deprivation can worsen GERD symptoms.[8]