Our Eyes, how things have changed
Posted on 5th April 2023 at 07:28
A couple of generations ago – or about 60 years ago if you prefer (!) – wearing glasses was quite unusual, although many older people had to resort to a little extra “help” with reading. Usually when their arms weren’t quite long enough to hold whatever they were trying to read at the right distance or the print had suddenly become much smaller (!). Perhaps you’ve experienced this for yourself as you’ve got older or heard someone else making similar comments. And we’d probably better stop there before we digress too much further…
Coming quickly back to the present day, things seem to have reversed. People NOT wearing glasses or contact lenses are quickly becoming the exception rather than the norm. Which, if you stop to think about it, is a huge change in a relatively short period of time.
The question is why?
Having made this observation to our lovely, now departed, Optician many years ago his answer was very straightforward. Our Eyes weren’t designed for the demands made by our modern lifestyle. In other words, predominately close up work under artificial light. It really is that simple and, if you think about it, makes complete sense.
Our Eyes – and bodies too (!) – were designed for active lifestyles outside in natural light, with regular periods of rest each day thanks to light free nights. The other big difference was that we weren’t top of the food chain, but one of the many options for predators much more powerful than us. And we’re talking about those both two legged and four legged... If that’s come as a bit of a shock to you, then you may want to stop and think about that for a while as, in evolutionary terms, this wasn’t that long ago either.
For these reasons distance vision was the priority, so we could see potential predators and threats as early as possible. This gave us the maximum time possible to either run away, hide or get ready to fight. And, in survival situations, a second or two makes all the difference. By contrast, near vision was – relatively – much less important as, by that time, it really was too late. In every sense of the word…
By contrast, modern lifestyles are centred around close vision and occur mainly inside, under artificial light. It’s easy to forget how much artificial light – starting with fires and candles before electricity was ever dreamed of – altered our days. Not only in what we could do because of the better light, but also by lengthening our days far beyond natural daylight. The end result of this is that our Eyes now work much harder each day and for much longer periods than ever before. So, it’s not that surprising that many more people are needing help on the vision front.
So, let’s take a quick look – no pun intended (!) – at theses changes and how affect our Eyes and vision.
Let’s start with the most obvious, our reliance on artificial light and the added strain this puts on our Eyes. Natural light is very different to that produced by light bulbs or your favourite electronic gizmo, not only in terms of colour but also wavelength. In very simple terms, sunlight provides full spectrum light. In other words, it contains all the colours of the rainbow. These effectively cancel each other out to create white light, otherwise known as sunlight.
In addition, the proportions of the different colours contained in natural light varies during the day. For example, the “softer” light at either end of the day is due to a predominance of red and orange tones.
Just as important is that natural light also has a longer wavelength. This means it generates less energy, making it easier – and less damaging – to the Eyes.
By contrast, artificial light doesn’t contain the full spectrum of colours, with those present depending on the bulb used. For example, LED and fluorescent lights provide mainly blue or yellow light with very little red. By contrast, the more traditional light bulbs give off mainly red light and very little blue.
This is important because the colour of the light determines its wavelength and the energy produced. Both red and yellow light have a longer wavelength which produces less energy. Blue light, on the other hand, has a much shorter wavelength and produces more energy.
What this means is that the shorter wavelength – and greater energy – of blue light gives it the greatest potential to damage our Eyes. This is because blue light damages the retinol contained within the photoreceptors in the Macula in the back of the Eye. Over time it destroys these photoreceptors and, as they can’t be replaced, can lead to long term damage to eyesight and, at worst, blindness. It’s known as Macular Degeneration and, sadly, is becoming much more common.
We’ve written about the hidden dangers of blue light before and the post can be found here.
Added to this, artificial light allows us to “stretch” our days well into the evening – or early morning (!) – so our Eyes are working harder and for longer than ever before. And this gets more so every year, as the latest gizmo encourages us to work – or socialise – smarter / harder / longer. The end result is that our Eyes have less and less time every day to rest and recuperate…
Finally, comes the switch from relying on our distant vision to near vision, particularly as all things electronic have taken centre stage in our lives. And we’re not just talking about TV’s and computers but all those electronic gizmos emitting blue light…
Without going into too much gruesome detail, particularly with Eyes (!), the Eye muscles are much more relaxed when we focus on something in the distance, unless the light is very bright and we then have to squint to reduce the amount of light entering the Eye.
By contrast, when we focus on something close to us – say a screen or book – then the Eye muscles have to contract to bring it into clear focus. Not surprisingly, this is much more tiring as far as the Eyes are concerned, even before adding in the extra strain from artificial light or longer days. Once again, one small change quickly adds to another, although not in a positive way…
So, what’s the answer?
Well, as always, the most important thing is to be aware of the issue otherwise nothing can be done. Next is to notice just how much time is spent under artificial light each day and, dare we say it, in front of all the blue screened gizmos, which may surprise you. You may not be working as such, but it all adds up.
Then, it’s just a case of a little common sense and making some simple changes on how you organise your day. To start taking regular breaks during the day, along with time outside in natural light. Cutting down the use of blue light gizmos generally, particularly later in the day, giving your Eyes a rest before going to bed. If you’d like some other suggestions, here’s the link again for our post on the hidden dangers of blue light.
While we don’t often stop to think about it, vision is our predominant sense. The sense we rely on, even in this technological age of ours. Giving our Eyes and ourselves a little extra tlc – and time off – each day may be exactly what we need on every level…
As always, the choice is yours.
Photograph by unknown author
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