What causes gastric reflux?

Gastric reflux, also known as gastroesophageal reflux disease (GERD), primarily occurs due to a weak or dysfunctional lower esophageal sphincter (LES). The LES is a muscle that acts as a valve between the esophagus and the stomach. When this muscle is not functioning properly or is weak, it can fail to maintain a tight seal, allowing stomach contents, including acid, to flow back up into the esophagus. This backflow leads to the characteristic symptoms of heartburn and acid reflux.

While factors such as overproduction of gastric acid, increased stomach pressure, and certain dietary choices like consuming spicy foods can contribute to the condition or exacerbate symptoms, they are not the primary cause of gastric reflux. The weakness of the LES is the fundamental issue that leads to reflux, making it the most direct and relevant explanation for the condition. Understanding the role of the lower esophageal sphincter is crucial in addressing and managing gastric reflux effectively.