The truth about Eyes

[wp_blog_designer id=”1″]5 things you didn’t know…

1. You can forget to blink

Ok, you can’t “forget” to blink as you’re not really aware of it in the first place, so apologies for the somewhat misleading title there, but certain situations can mean you blink less. Healthy adults blink 10-15 times a minute, however when using a screen our blink rate has been observed to reduce by up to 60%.  This may not sound like much but have you ever felt your eyes being tired or dry after long stretches on the computer? With fewer blinks our tear film isn’t renewed as efficiently and our eyes become dry. To avoid this, and other problems relating to extended screen use the 20/20/20 rule – every 20 minutes, focus on something 20 metres away for 20 seconds

2. Half of world blindness is easily treatable

Yes half. According to the World Health Organisation (WHO) cataracts are responsible for 51% of world blindness. Cataracts are the gradual clouding of our lenses as we age and in most rich countries this is cured with a simple operation but in many countries this surgery is still not accessible. We have some great charities such as Sight2Save who are working hard to treat avoidable blindness all over the world (the link to donate is below) but with an aging population, help is more important now than ever.

http://www.sight2save.org/donate/

3. Babies can’t cry

Erm what? All babies do is cry (and poop) right? Well until they reach anywhere from one to three months old, newborn babies do not produce enough tears to cry, only just enough to lubricate the eye and replenish the tear film. This doesn’t mean they can’t sound like they’re crying, as many new parents will tell you.

4. You don’t have blue eyes

So if you have brown eyes like the majority of us this may not be huge revelation, but for those of us thinking our eyes are blue, it’s more accurate to say they’re not brown. Brown eyes are brown because of melanin, the same pigment that colours the skin. People with “blue” eyes have much less melanin in their pigment epithelium (a layer in the iris) causing shorter wavelength blue light to scatter more and reflect more easily, giving the impression that the eyes are blue. This effect is seen in a lesser extent for green or grey eyes. In fact, having blue eyes at all is due to a genetic mutation about six to ten thousand years ago, so if you’re blue-eyed and see another blue-eyed person, you are (very distantly) related.

5. Red eyes in photos are caused by blood vessels.

In case any of you hadn’t noticed by now, in some photos your pupils look like small, bright red dots. For most of you this isn’t because you’ve been possessed by a demon but is the camera flash reflecting off your choroid. The choroid is the layer just below the retina made up of lots of blood vessels.

Well, that’s it for Today. We hope we’ve taught you something you didn’t already know. Watch this space for our next blog!