What is the main purpose of the vocal folds during respiration?

The primary purpose of the vocal folds during respiration is to protect the airway from aspiration. When we breathe, the vocal folds are positioned in such a way that they can close partially to prevent foreign objects, liquids, or food from entering the trachea and reaching the lungs. This action is critical for maintaining airway safety and ensuring that only air passes into the trachea, while also providing a mechanism to initiate a cough reflex if something does enter the airway.

Although the vocal folds certainly have roles in sound production, pitch variation, and airflow regulation, these functions are secondary to their fundamental protective role. The closure of the vocal folds when swallowing or during certain phases of breathing is essential for preventing aspiration pneumonia and other respiratory issues that can arise from materials entering the airway.