What Actually Causes Itchy Eyes?
For decades, doctors and opticians alike were puzzled by the question of "what causes itchy eyes?". Sure - the reason why our eyes itch has been known for a long time, however it wasn't until about 1970 or so that we actually began to discover the scientific and biological processes involved in the actual onset of the "itch".
Thankfully, with modern day analytical tools and powerful microscopes - we are now able to reveal exactly what it is that actually causes the itchiness in the eyes, as a result of allergies, irritation, or dryness. What is particularly interesting is that the mechanism by which the itchiness is brought about is something which most people would never even imagine was possible.
Let's take the opportunity in the rest of this article, to study the exact biological process at play when we have irritated eyes - so that you can indeed understand what is going on at a microscopic level the next time you have itchy eyes.
As Simple As Sand
To understand what is going on with itchy eyes, you first need to imagine a bag with a tiny bit of sand at the bottom. When you move the bag around, the tiny bits of sand also move around the bottom of the bag - causing the slightest bit of friction in the process.
Now, just imagine that the bag is your eye socket - and the sand is about 100 times smaller than a real grain you would find on a beach. What you have just seen is the exact reason why itchiness develops in the eye.
As irritants and pollutants build up in the lower parts of the eye - they are sometimes trapped in the tiny folds of the mucus membranes surrounding the eye itself. Unfortunately in this case, the natural tears which the eye produces are unable to wash away these microscopic particles, and hence they end up grouping together. They them form small "grains" - which move around the eye ever so slightly and cause friction on the inside of the eyelids.
To us, this movement is experienced as an itch. The more and more build up which occurs in the eye - the more severe the itchiness gets. That's all there is to it!