Why Do We Get ‘Sleep in Our Eyes’?
How often do you wake up and wipe away ‘sleep’ from your eyes? That natural gunk is always there, but why is it there? What is the purpose of this yellow-y substance? It’s all down to mucus, bacteria, dust, dirt, and dead skin cells. SciShow have posted a wonderful video to explain “sleep boogers” (the American term for ‘sleep in our eyes’).
The ‘gunk’ which you may have experienced doesn’t actually have a scientific name. Instead, it’s generally referred to as a type of gound or rheum, terms used for discharge from mucus areas like your nose or mouth.
Michael Saranda, host of the SciShow, explains that “rheum” is always present in your eyes. Each eye is protected by a tear film, made up of a watery mucus with an oily layer on top. When we’re awake, anything which gets in your eye is caught by the oily film and washed away when you blink.
When we’re asleep, you’re not blinking. All of the mucus and dirt builds up, which mixes with the oil from the tear film. All of this collects in the corner of your eye, which creates the “rheum”, or ‘sleep’ (“eye boogers”, if you’re American).
The consistency of the ‘sleep’ in your eye depends on your tear film. Those who suffer allergies or sensitive eyes tend to have more liquid, goopier rheum, this is because they rub their eyes more and produce more mucus.
So, there we have it, science quashing the Sandman theory. If you want to understand it a bit further, we recommend you watch the SciShow video below!