Scientists have been studying the effect of blue light — which can be found in digital devices such as screens — on our body and brain for decades, and even today it is fascinating. While some blue light can be helpful and even essential to humans, a lot of it can cause serious issues. This includes direct harm such as eye strain or headaches, but also indirect harm, such as disrupting focus and depriving sleep quality. Here we delve into these problems more deeply.
1. Eye strain
Blue light is more likely to harm people who spend much time staring at screens, with the average person doing so for around seven hours a day. One of the biggest problems is eye strain. Otherwise called asthenopia, this disrupts many daily activities, whether it be your concentration and productivity at work, or relaxation after. If neglected, asthenopia will worsen and can contribute to long-term vision issues such as cataracts and age-related macular degeneration (AMD).
What are the most common signs of eye strain?
The most common symptoms of eye strain include:
- Sore or burning eyes
- Dry eyes
- Blurred vision
- Increased sensitivity to light
- Lack of concentration
- Unable to keep your eyes open
Although these symptoms may relate to other ailments, if there is a correlation and consistency between experiencing these following periods of digital exposure, you may want to consider contacting your GP.
2. Dry Eyes
Blue light has been shown to be associated with dry eyes. This eye disorder is intensified the more you are exposed to light sources that emit high amounts of blue wavelengths, such as screens from monitors and phones.
Dry eye refers to a condition where the eyes are unable to produce enough tears to keep the eyes lubricated. Staring at a glaring screen for a long time causes an imbalance on your eyes, resulting in less-frequent blinking. This, in turn, washes less moisture over the eyes and causes them to dry up.
If left untreated, dry eyes may lead to eye inflammation, abrasion of the corneal surface, corneal ulcers and vision loss.
3. Blurred Vision
Whether it’s an essay, spreadsheet or graphic design project, it’s easy to lose track of time as you are focused on your work, and therefore, your screen. However, not giving your eyes a proper break from the blazing screen can lead to blurred vision. This is because our natural eyes’ filters are not fit for blocking blue light over long, sustained periods.
When nothing is done to address the cause of the problem (the screen), the symptoms will continue to recur and perhaps worsen with future digital screen use.
There is a specific neural pathway from the eyes to the brain, separate from vision, that causes blue light wavelengths to worsen headache pain. It’s therefore no surprise then that numerous pieces of research show that blue light can be seriously harmful to people prone to headaches and migraines.
An overexposure to blue light leads to great discomfort, a higher perception of pain and throbbing, and even the spreading of headache across the brain. This does not even consider that the colour of light can increase other symptoms of migraines too, such as photophobia, light sensitivity and nausea.
5. Lack of focus
Although there are many other factors that can affect your focus, whether it be restlessness, dopamine addiction or simple boredom, blue light is also capable of doing so. This is due, in part, to the ailments discussed previously, which make concentrating at your screen difficult. You have deadlines to meet, work to finish, games to enjoy, but your health should always be the priority.
Research published in the International Journal of Engineering and Technology made a number of discoveries when it comes to blue light and concentration. It found that the memory of participants who performed with a blue light filtered screen was better, showing that exposure affects the ability to hold information in the mind and interferes with short term memory. Moreover, in sustained attention tasks, the reaction time of standard screen participants was slower than people who used the blue light filter screen. Therefore, this could indicate that blue light exposure disrupts the ability to focus on a single task.
6. Quality of sleep
This is a big one. Blue light disrupts our circadian rhythm, otherwise known as our natural body clock. The circadian rhythm operates by prompting the body to secrete sleep-inducing hormones when it’s dark, and inhibits its production as it gets light. The most well-known of these is melatonin. In other words, when you open your curtain and absorb the natural light from the sun in the morning, melatonin is inhibited. Then, as you settle in for the evening and the slow darkness starts to envelop your home, the melatonin tap is turned back on.
However, if you expose yourself to devices through the day and then into the evening, your brain could start getting confused, treating the blue light from your screens the same as sunlight and prolonging its inhibition of the secretion of melatonin as a result. In short, synthetic blue light from screens tricks our brain into believing that it’s day-time, which makes falling asleep more difficult. This, in turn, lowers our sleep quality, which has all kinds of adverse effects.
How to protect yourself from the negative impacts of blue light
There are two primary ways to curb almost all of the effects discussed above.
Take regular breaks from screens
The first one is to make sure you take regular breaks from screens. If you struggle with losing track of time, try implementing a timer in your work routine. Set it for every 30 minutes, and when it rings, get up and turn away from it for a few minutes. Whatever you do though, don’t send this ‘break’ time scrolling on your smartphone. That kind of defeats the purpose.
Use products that protect against blue light
The next step is to make use of physical products that create a protective barrier between the blue light emitted by the screens and your eyes. These come in the form of anti-blue light screen protectors for laptops/monitors and phones, as well as anti-blue light glasses. Using this new tech reduces the blue light impact almost entirely, so you can be sure that their effect is minimal. Coupling regular breaks with the smart tech is the safest way to ensure you are kept from long-term harm.