We blink unconsciously and the average person blinks about 15 to 20 times per minute. If you do the math, a normal person blinks at least 14400 times per day (taking an 8-hour sleep time out of the equation). Carry on the math, if a blink took 0.3 second, that would simply add up to 72 minutes per day. Can you believe that we spend more than an hour a day shutting our eyes while we are awake? Sounds crazy huh?
Why do we blink?
Imagine there’s a puddle of water outside in the sun. What happens after a while? It evaporates.
The same goes for your tear film. Your tear film, which consists of 3 special layers of different elements, breaks up after a while. The tear film is made up of a fat layer, an aqueous layer and a mucous layer. For the sake of simplicity, you do not have to understand what each layer does.
But you do have to understand the functions of the tear film in general. Your tear film is essential in 4 main ways:
- provide nutrients to the transparent front part of the eyes (cornea)
- Flushes dusts and debris away
- defends against harmful microorganisms because it contains antibodies and antimicrobial enzymes.
- allows sharp vision by providing a smooth surface over the cornea.
Your eyelids act as a pair of windscreen wipers basically. Every time the nozzle sprays water to wash away the debris/dusts on your windscreen, the wipers quickly swipe across to spread a layer of water evenly over the surface of the windscreen.
The human eyes have similar nozzles around them, and each nozzle sprays different things. We have a lipid nozzle that sprays fat, an aqueous nozzle that sprays water and a mucous nozzle that sprays mucin. Then the eyelids acts quickly to mix and spread all these elements over the eyes which become the tear film. This mechanism keeps repeating every time the tear film breaks up to make sure the eyes are well covered with a layer of protective tear film.
In brief, we blink frequently to make sure a new layer of tear is formed every time it breaks up for the optimal functioning of the eyes.
What happens if I blink less than I should?
Going back to the windscreen wipers analogy, if you blink LESS than you should, the debris on the windscreen can’t be got rid of efficiently. On the other hand, the area of the windscreen that requires the water from the nozzles for ‘nutrients’ would not be getting anything.
Worst still, the water sprayed from the nozzles are flowing away.
The same is true for the eyes. The tear’s drained away before it even reached its designated area (cornea). As it turns out, the renewal process of the tear film is impeded which could possibly lead to dry eye syndrome in the long run.
People FORGET to blink nowadays
Before you lash out at me and say how could one forget to blink…
Numerous studies have shown that we tend to blink less than we should while staring at a VDU (computer, tablet, smartphone etc.). Consequently, dry eye syndrome has been on the rise in recent years with people reporting symptoms including a gritty feeling and even sore eyes.
What should you do if you spend a lot of time in front of a screen? You can learn it HERE.
However, if you experience any dry eye symptoms and you are concerned about it, it’s really best for you to consult a qualified, registered optometrist. You can find the nearest optometrist HERE if you reside in Malaysia and Singapore.