The thought of tears may stir up some negative feelings, like that windy day your eyes wouldn’t stop watering from allergies, or that day you cried your eyes out for one reason or another. But the fact is, tears are an essential component of healthy and functioning eyes—they’re not just for crybabies! Here’s why.
Without tears, your eyes would feel as dry as a desert.
This goes without saying, but imagine trying to blink without tears. It would be like rubbing sand paper on your skin. Well maybe not quite like that, but it definitely wouldn’t feel good.
Dry eye, a common and often chronic problem, can occur from people either not producing enough tears or having a poor quality of tears. The reason tears make your eyes feel good can be explained by the function of each layer of tears:
- Outermost layer – The oily layer that acts as a sealant to keep your tears from evaporating. It is produced by the meibomian glands.
- Middle layer – The aqueous layer that delivers vitamins and minerals to your cornea. It is produced by lacrimal glands.
- Innermost layer – The mucous layer that keeps the tears attached to the eye itself. Without this function, imagine tears dripping off the front of your eye as opposed to seeping out the corners or falling off the lower lid. It is produced by goblet cells.
FUN FACT: There are three kinds of tears.
- Basal tears are the most general type of tear that keeps your eyes moistened and functional.
- Emotional tears (psychogenic tears) appear in response to sadness, stress, joy, or other intense emotions. They carry more protein-based hormones than the other types and help to cleanse your body of the chemicals caused by pent-up emotion.
- Irritant tears (reflex tears) appear in response to pain or a foreign object in the eye.
Nourishment for your eyes comes in the form of tears.
Like the rest of your body, your eyes need nutrients to stay healthy and alive. “Because the cornea doesn’t have any blood vessels of its own, it’s up to the tears to keep it nourished,” says Dr. Udvari. Here are a few of the life-giving goodies hiding in our tears:
- Omega-3 fatty acids, which keep your eyes lubricated and help prevent dry eye syndrome
- Lysozymes, which are the healing factors of the eye and fight off bacteria and viruses
- Folic acid (vitamin B9)
- Sodium, which helps maintain the corneal epithelium
FUN FACT: Why does your nose run when you cry?
Your eyes and nose are connected by the nasolacrimal duct. This explains why your nose runs when you cry. Dr. Udvari outlines tears’ trajectory like this:
- Created in the lacrimal glad and conjunctiva
- Travel to drains in the corners of your eyes near your nose called puncta
- Travel to lacrimal canal
- Fill up the lacrimal sac
- Drain into nasolacrimal duct (a.k.a. tear duct)
- End at your nose
Joseph D. Udvari, Jr., O.D. FAAO, is a VSP doctor at Complete Family Vision Care in Moon Township, PA. Dr. Udvari has served on many Optometric boards and has been a member of the American Optometric Association. He’s extremely active in clinical studies for contact lenses, has served as a vision consultant for kids and athletes, and has published articles in the Journal of the American Optometric Society and the Optometric Management—including topics such as dry eye. His accomplishments also include several professional awards and the designation of Fellow of the American Academy of Optometry.
The content of this article is for general informational awareness purposes only. Please consult your eyecare doctor or physician for actual advice.