Facts About Tears

Tears serve many purposes and are constantly produced by the eyes. In fact, on average, a person produces 15 to 30 gallons of tears each year. Tears are essential for maintaining the health of the eyes and have multiple functions, including lubricating the eyes, protecting the cornea, washing away irritants, and communicating emotions.

You Have More Than One Type of Tear

The human body produces three types of tears, each serving a distinct purpose:

Basal tears: Basal tears are present in the eyes all the time. They act as a constant shield, protecting the cornea and keeping dirt and debris away. Basal tears also provide lubrication and nourishment to the eyes.
Reflex tears: Reflex tears are produced in response to irritants such as smoke, foreign bodies, or onion fumes. These tears are released in larger amounts than basal tears and may contain more antibodies to fight bacteria. Reflex tears help wash away harmful substances from the eyes.
Emotional tears: Emotional tears are produced in response to various emotional states, including joy, sadness, and fear. Some scientists suggest that emotional tears contain additional hormones and proteins not present in basal or reflex tears. These tears play a role in expressing and communicating emotions.

Tears are not just saline; they have a complex composition similar to saliva. They contain enzymes, lipids, metabolites, and electrolytes. Each tear has three layers:

An inner mucus layer that keeps the tear attached to the eye.
A watery middle layer, which is the thickest layer, responsible for keeping the eyes hydrated, repelling bacteria, and protecting the cornea.
An outer oily layer that keeps the tear’s surface smooth for clear vision and prevents the other layers from evaporating.

How Your Body Makes Tears

Tears are produced by the lacrimal glands located above each eye. When you blink, tears spread across the surface of the eye, keeping it moist and protected. The tears then drain into puncta, tiny holes in the corners of the upper and lower eyelids. From there, tears travel through small canals in the lids and down a duct before emptying into your nose. Once in the nose, tears may either evaporate or be reabsorbed.

In some cases, babies are born with a blocked tear duct, a condition that usually resolves on its own. However, in adults, a blocked tear duct can occur due to various reasons, such as eye infections, swelling, injury, or tumors.

Excessive production of emotional or reflex tears can overwhelm the lacrimal drainage system, causing tears to spill out of the eyes, run down the cheeks, and sometimes even dribble out of the nose.

You’ll Make Fewer Tears as You Get Older

As a person ages, the production of basal tears slows down. This decrease in tear production can lead to the development of dry eye, a common problem characterized by insufficient lubrication and moisture in the eyes. Hormonal changes, especially during pregnancy and menopause, can contribute to dry eye. Additionally, wearing contact lenses and certain medications can cause or worsen dry eye symptoms.

Dry eye may also increase the risk of developing blepharitis, a condition characterized by irritation or swelling of the eyelids.

If you experience dry eye, it is important to consult with an ophthalmologist. They can recommend various treatments and lifestyle changes to help keep your eyes moist and alleviate dry eye symptoms. There are also several simple things you can do at home to promote eye moisture, such as using artificial tears, practicing good eyelid hygiene, avoiding excessive screen time, and maintaining a healthy diet rich in omega-3 fatty acids.

Overall, tears play a crucial role in maintaining the health and well-being of our eyes. They serve multiple functions, from protecting the cornea to expressing emotions. Understanding the different types of tears and the factors that can affect tear production can help us take better care of our eyes and ensure optimal eye health throughout our lives.