A high level of blue light wasn’t something our prehistoric ancestors had to worry about, but recent developments in technology now mean that we are surrounded by blue light. But what exactly is blue light, what’s the problem with it and how can blue light glasses help?
It was not too long ago – it’s certainly within living memory – that in the UK we had two main TV channels that didn’t broadcast beyond midnight. TVs were boxes in the corner of the room, unlike today’s large, flatscreen TV screens that show our favourite shows, on-demand, every hour of the day.
Neither were there such things as mobile phones. In fact, when the landline was invented, it took many years before the telephone became a feature in most homes.
There were no tablets, PCs and laptops, even though the computer was invented in 1833. It didn’t look anything like the desktops of today, however. It was huge, dominating a very large room and was known as the Difference Engine.
Computers are now everywhere, automating activities that humans have traditionally done themselves.
What this does mean is that we are surrounded by more blue light, some of which is intense and to which we are exposed for long periods of time. Average screen time in the UK is just over three hours a day or 50 days a year staring at a screen. For the younger age group of 16 to 24-year-olds, screen time significantly increases. And that means, exposing our eyes to a lot of blue light.
Every time you use your phone to send a quick text or message, you expose your eyes to it. Every time you sit at your PC or laptop, you expose yourself to it. And those games you play on your tablet? They also expose your eyes to blue light.
What is blue light?
Blue light is everywhere and always has been. PCs, laptops and other devices with screens all emit a blue light. And because we use these screens for a long time every day, it is causing us problems.
Blue light is part of the natural light that is all around us. Without getting into complicated physics, sunlight is a mix of red, orange, yellow, green and blue light rays, although there are many shades of these colours. The variations in shades depend on energy and wavelength, also known as electromagnetic radiation. When these colours combine, “whitelight” is created.
photo credit Ground State Curiosity
You may have studied the light spectrum as part of your school’s science lessons. If so, you’ll remember that there is an inverse relationship between the wavelength of light rays and the amount of energy they have.
So, long wavelengths have less energy, and shorter wavelengths have more energy. Red rays have longer wavelengths and less energy. Blue light has shorter wavelengths but a lot more energy.
Exposure to too much blue light has a ‘burning’ sensation, the reason why the blue light emitted from computers, tablets and phones is considered problematic. This isn’t just a problem for technology. For example, snow blindness is the exposure of the unprotected eye to the bright, reflective light of snow which, if you closely examine it, is blue.
The same is true for sunbeds and similar pieces of equipment that emit blue light - something that is also referred to as ultraviolet or UV light. It is the high level of energy in blue or UV light that causes us to tan or, in many cases, burn.
What is the problem with blue light?
The problem is that with technology becoming an increasing feature of everyday life, we are exposing our eyes to even more blue light. Whilst the energy levels don’t ‘burn’ our eyes, they do cause us other problems.
We know that blue light disrupts our sleep. Most of us are being exposed to far too much blue light. There are studies that show blue light inhibits or reduces the production of melatonin, the hormone that regulates the circadian rhythm. This is essential for sleep.
Research shows that in the couple of hours before bed, we start to produce more melatonin naturally, a signal to the brain and body to start slowing down in preparation for sleep.
Blue light is thought to suppress melatonin for twice as long, affecting the circadian rhythm - meaning for you, falling and staying asleep is more difficult.
It isn’t just the use of technology before bed that could be interrupting your sleep. Some styles of lighting also emit a level of blue light that could be inhibiting a soporific state that we need before bed.
If you feel more stressed than usual, it could be that your increased exposure to blue light is also triggering an increased production of cortisol, the hormone that alerts the body it is under pressure. This too affects sleep, in particular short-wave sleep which is also known as deep sleep. Higher levels of cortisol means you are more likely to sleep ‘lightly’ with frequent waking. In other words, you’re not getting the restful night’s sleep you need to wake refreshed, alert and ready for another day.
There is also emerging evidence that concentrated blue light from excessive use of screens could be resulting in damage to the eyes. As yet, the research sphere in this area is small but early studies suggest that there is a raised risk for eye diseases such as cataracts and age-related issues such as macular degeneration.
What are blue light glasses?
Blue light blocking glasses are specially crafted to block or filter out the blue light given off by digital screens. They can also reduce glare and although you may not notice they could be making a difference to your sleep pattern too.
They look, in the main, as an ordinary pair of glasses. And so if you choose to wear them at work, no one else would know that they are ‘special’ glasses.
Earlier examples of blue light glasses consisted of tinted yellow glass or plastic lenses. These are still available, although they tend to be used in sporting circles, such as cyclists, and they are also referred to as driving glasses.
Do blue light glasses work?
Adverts for blue light glasses seem to be popping up everywhere. People who have put them to the test, however, say that wearing blue light glasses was beneficial, including being more aware of how much time they spend on various devices.
What you don’t want to do, however, is rely on blue light glasses as a tool for ‘allowing’ you to spend more time on your PC, tablet and smartphone. You still need to be aware of screen time and making sure you look after your eyesight by allowing your eyes to rest.
As a tool for helping your eyes, however, when working or using screens is unavoidable, blue light glasses would be more than helpful.
How to stop blue light from affecting your sleep
We need to be aware of just how much our exposure to concentrated levels of high energy blue light is affecting our circadian rhythm and what we can do about it. Here are a few of our suggestions:
· Wear blue light glasses – available in a range of styles and varying price points, some people believe that blue light glasses are beneficial. If you spend most of your day working on screens, they may help to filter some of the blue light your eyes are exposed too. Ophthalmologists also advise us to use the 20-20-20 rule – looking up every 20 minutes from your screen to a point 20 minutes away for 20 seconds. We’ve designed our own, that block 94.33% of blue light wavelengths. You can find them here.
· Be more aware of screen time – we expose our eyes to many hours of screen time in any given day, for work and pleasure in many instances. Being more aware of screen time and making a point to move away from screens will be beneficial even if you aren’t struggling to get to sleep.
· Make the bedroom a tech-free zone – your bedroom should be a calm, yet welcoming room that encourages you to wind down after a busy day. From the position of furniture to interior design style, there are many visual aspects you can add to the bedroom to make it a pleasant space. But there are also things you need to remove, and blue light is one of them. That means finding a new place to charge your phone or ditch the tablet in favour of a printed book to read at night.
· Remove your phone from your bedtime routine – melatonin is an important hormone and for anyone struggling to get to sleep, and to stay asleep, encouraging our brains to recognise its signal and start slowing down is crucial. If you plan on retiring at 10 pm, switching off your phone or not using it after 8 pm could help in that your body will start to secrete the right level of melatonin. Combine this with a restful bedtime routine and you may find that after a few days of practising this re-established habit you drift off to sleep without any problem.
Will blue light glasses help your sleep pattern?
Along with a comfortable, supportive pillow, soft bedlinen and the pleasant, warm surroundings of your bedroom, using blue light blocking glasses during the day, along with reducing screen time, could certainly have a beneficial impact on how fast you can get to sleep and the depth of sleep you’ll experience.