Why Are Tears Important?
Tears provide your eyes with moisture, nourishment, and protection. They keep your eyes healthy and your vision clear. Dry eye can occur when your eyes don’t have the right amount of tears or if you have an unhealthy tear film.
Healthy Tear Film
Tears are composed of three layers of the tear film and are made by tear glands. Tear glands are located in the upper and lower eyelids. The tears that they produce are drained from your eyes through tear ducts, also known as punctums.
The tear film is a thin coating that covers the surface of your eyes. The tear film keeps your eyes moistened and comfortable; protects the surface of your eyes from dirt, dust, and other small particles; and helps to create a smooth surface so your eyesight stays sharp and clear.
The tear film is made of oily, water, and viscous layers. The oily layer prevents the tear film from drying up. The water-based layer contains water and nutrients to keep eyes healthy. The viscous layer is made of a thick, clear liquid. When you blink your eyes, the viscous layer spreads the tear film over the eyes to keep them lubricated and moist. Both the volume of tears and quality of the tear film are important to keep your eyes healthy and feeling comfortable.
Unhealthy Tear Film
Changes in the oily, water, and thick liquid layers can create an unhealthy tear film causing an imbalance of the eye’s natural lubrication process. This can be caused by a lack of tears, poor ‘health’ or quality of the tears or tear layers, or high rate of draining of the tears from your eyes. Whatever the cause of imbalance, this can lead to areas of dryness causing damage to the eye’s surface and your vision.