lower esophageal sphincter
Quick Summary
The lower esophageal sphincter (LES) is a muscular ring located at the junction of the esophagus and the stomach. This sphincter plays a crucial role in digestion by preventing stomach contents from flowing back into the esophagus, a process known as gastroesophageal reflux.12
The LES normally remains closed, opening only to allow food to pass from the esophagus into the stomach or to release gas (belching) or vomit. When the LES functions inadequately, stomach contents can reflux into the esophagus, causing symptoms like heartburn. Factors such as obesity, pregnancy, and certain foods can contribute to LES dysfunction and reflux.12
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esophagus…or lower, end is the lower esophageal sphincter.
Read More…or lower, end is the lower esophageal sphincter.
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…end of the esophagus, the lower esophageal sphincter relaxes and food enters the stomach; the sphincter then closes again to prevent reflux of gastric juices and food materials.
Read More…end of the esophagus, the lower esophageal sphincter relaxes and food enters the stomach; the sphincter then closes again to prevent reflux of gastric juices and food materials.
Read More