The esophageal sphincter is a muscular ring located at the junction of the esophagus and the stomach. Its main job is to control the flow of food and liquids from the esophagus into the stomach, preventing backflow or reflux. This helps protect the esophagus from stomach acids, which can cause irritation and discomfort. There are two main types of esophageal sphincters: the upper esophageal sphincter and the lower esophageal sphincter. The upper sphincter helps keep air from entering the esophagus during breathing, while the lower sphincter prevents stomach contents from flowing back into the esophagus. Proper functioning of these sphincters is essential for healthy digestion and overall gastrointestinal health.