How do eyelashes and eyebrows protect your eyes?

Those pretty hairs that dot your eyelids do more than just accentuate. Turns out, they play a crucial role in protecting your eyes. But what are your lashes protecting you from, exactly?  

Dust particles, sand, identity theft, multi-level marketing schemes, phishing, supervillains, and other bad guys… mostly of the Billie Eilish kind. ;) Jokes aside, your eyelashes and eyebrows work around the clock to keep your eyes healthy and safe. Here’s everything you need to know about these little superheroes. 

Eyelashes are like a cat’s whiskers, extra-sensitive to the objects around them. Your eyelashes can sense when an object is too close (such as a speck of dust or oncoming insect) and tell your eyelids to shut to protect the eyes. Your eyelashes also help shield your eyes from bright lights, although they may not be as strong as a pair of polarized sunglasses. 

How many eyelashes do you have? 

While we may not be able to physically count your lashes because doing so would be a little weird, we can say that the average amount of lashes per human is around 90 to 150 on the upper lids and 70 to 80 on the bottom lids. That’s a lot of lashes. 

How many eyelashes do you lose each day? 

The average set of lashes grows around 0.12 to 0.14mm (about .005 inches) every day, which is about two times slower than the hairs on our head. You can shed anywhere from one to five natural lashes per day. Makes you wonder where all those tiny hairs end up.  

What about eyebrows? Are they protective too? 

Ever wondered what the purpose was of those forehead caterpillars? Turns out they’re protective too. Eyebrows keep sweat and rain away from our eyes so we can keep seeing. Even the way our eyebrows grow naturally wicks moisture away from the center of the eye toward the side of the head. We also use our eyebrows to express emotions and to better recognize each other’s faces.  

Now that you know how important your eyelashes and eyebrows are to your eyes, did you thank them today for their hard work? They hardly batted an eye.  

Sources: 

  1. https://www.ncbi.nlm.nih.gov/books/NBK537278/ 
  2. https://www.healthline.com/health/why-do-we-have-eyebrows