Many people experience their eyes watering when they yawn, a common and often curious bodily response. This phenomenon is a natural, involuntary reflex that stems from the mechanics of yawning itself. Understanding why this happens involves the pressure exerted by facial muscles and the eye’s tear system.
The Link Between Yawning and Tearing
The act of yawning causes a cascade of muscle contractions throughout the face and jaw. Specifically, the forceful stretching and contraction of facial muscles, including those around the eyes, play a direct role in producing tears during a yawn. These muscles, such as the orbicularis oculi, tighten and put pressure on the lacrimal glands, which are responsible for tear production. This pressure can temporarily “squeeze” out tears that are already present in the glands, leading to the watery sensation.
Beyond stimulating tear production, the muscle contractions during a yawn can also affect the tear drainage system. The movement and pressure from yawning can momentarily disrupt the normal flow of tears through the tear ducts into the nasal cavity. This temporary blockage or disruption means that tears accumulate on the eye’s surface, eventually overflowing and becoming visible as watery eyes. This combination of increased tear release and impeded drainage contributes to the common experience of tearing during a yawn.
The Eye’s Tear System
The eye’s tear system is a sophisticated mechanism designed to keep the eyes lubricated, clean, and protected. Tears are primarily produced by the lacrimal glands, which are almond-shaped structures located above the outer corner of each eye. These glands continuously secrete basal tears, a thin layer of fluid that coats the surface of the eye, providing lubrication and washing away small irritants.
Once tears have served their purpose, they typically drain away through small openings called puncta, located in the inner corner of the eyelids. These puncta lead into tiny tubes called canaliculi, which then connect to the lacrimal sac and finally to the nasolacrimal duct, draining tears into the nasal cavity.
When Tearing Might Be a Concern
Tearing up while yawning is generally a normal and harmless physiological response. It is a common occurrence and does not typically indicate a medical problem. However, if excessive or persistent tearing occurs frequently, even without yawning, it might suggest an underlying issue that warrants attention from a healthcare professional.
Signs that tearing might be a concern include persistent watery eyes accompanied by pain, redness, blurred vision, or discharge. Constant tearing that is not related to yawning or other obvious triggers, such as allergies or dry eye syndrome, could also indicate a need for medical evaluation. In such cases, consulting an eye doctor can help determine the cause and appropriate course of action.