Swallowing, or deglutition, is the complex process of moving food from your mouth to your stomach. It involves a coordinated series of muscle contractions in the mouth, throat, and esophagus.
Stages of Swallowing
The process can be broken down into three main stages:
1. Oral Phase (Voluntary):
This stage begins when you decide to swallow. Your tongue pushes a bolus (a mass of chewed food) towards the back of your mouth and into the pharynx (throat). This is a voluntary action under your conscious control.
2. Pharyngeal Phase (Involuntary):
Once the bolus enters the pharynx, the process becomes involuntary. Several reflexes are triggered:
- The soft palate elevates, closing off the nasal passages to prevent food from entering your nose.
- The epiglottis folds down, covering the opening to your trachea (windpipe) to prevent food from entering your lungs.
- The upper esophageal sphincter (a ring of muscle) relaxes, allowing the bolus to enter the esophagus.
3. Esophageal Phase (Involuntary):
In this final stage, peristalsis—a series of coordinated muscle contractions—moves the bolus down the esophagus to the stomach. The lower esophageal sphincter then relaxes to allow the bolus to enter the stomach.
The process of swallowing, also known as deglutition, involves the movement of substances from the mouth (oral cavity) to the stomach via the pharynx and esophagus. Swallowing is an essential and complex behavior learned very early in development.
Practical Insights
Understanding the swallowing process is crucial for diagnosing and treating swallowing disorders (dysphagia). Dysphagia can lead to choking, aspiration pneumonia (food entering the lungs), and malnutrition.
