What is blue light? Is it harmful to our children’s eyes?

What is blue light and is it harmful to our children’s eyes?

child using devices in the dark

For all the parents reading this, many of you may know that your children are constantly exposed to blue light. It is emitted from smartphones, tablets, television screens, and even indoor lights, such as light-emitting diodes (LEDs) and fluorescent lights – but did you know that they are also exposed to blue light when they are outdoors? The sun is the biggest source of blue light and your little ones have been getting most of their exposure to blue light when they head outdoors during daylight. Given that we know that outdoor time during childhood is encouraged for maintaining good eye health and that children are exposed to sunlight on a daily basis, you may reasonably be wondering: “Is blue light really all that harmful to my child’s eyes?”

The bright side: blue light emitted from the sun

Exposure to natural blue light emitted from the sun does not seem to be harmful – during the daytime, it can improve energy and alertness and it boosts your mood and productivity! Beyond that, it helps regulate the body’s circadian rhythm or body clock, which helps you stay awake during the day and go to sleep at night.

Higher exposure to blue light during the day causes the brain to secrete less melatonin – the major sleep hormone. And as it gets progressively darker, closer to bedtime, melatonin production increases. This makes you sleepy and signals that it is time to go to bed and get a good night’s sleep. So clearly natural blue light plays a key role in our normal functioning.

The dark side: blue light emitted from screens

There are important differences between the way in which we are exposed to blue light from the sun and to that of digital screens, and this makes all the difference to why one is healthy and one is not. Although screens only emit a fraction of blue light compared to the sun, the excessive and prolonged use of device screens at extremely near distances to your eyes results in longstanding, adverse effects. Let’s look at some of these effects.

Digital eye strain

Excessive exposure to blue light emitted from screens may lead to digital eye strain, a condition all known as computer vision syndrome, which includes eye redness, irritation, trouble focusing, blurred vision, and headaches. How exactly does this happen?

When blue light from screens enters the eyes, it scatters and increases the effort needed by the eyes to maintain focus. This increased effort may contribute to eye fatigue and eventually eye strain. Long periods of exposure to the blue light from screens also reduce blinking rate, which leads to a decrease in tear production and an increase in tear evaporation which eventually may result in dry eyes.

A poor night’s sleep

poor sleep from excessive blue light

As it turns out, screens may also be to blame for a poor night’s sleep as well as the ensuing grogginess you and your children suffer from the next day! Research has shown that the blue light emitted from smartphones and tablets suppresses the production of melatonin, mimicking the effect of sunlight on your brain. It’s easy to see how suppressing melatonin artificially through screens at night time can cause serious sleep disruptions.

This effect can be likened to jet lag: your sleep cycle is disrupted, and you find it difficult to fall and stay asleep at your usual times, resulting in poor quality sleep and sleep deprivation.

Startlingly, research shows that even small amounts of sleep deprivation have comparable effects on brain function to those of alcohol intoxication. In fact, a 17 – 19 hour period of no sleep (in other words like waking up at 7 am and going to sleep at 1 am – something many of us are guilty of) is equivalent to a blood alcohol concentration of 0.05%!

To make matters worse, according to the National Sleep Foundation, the effects of inadequate sleep are more disruptive in children. Children who do not get enough sleep find it difficult to wake up in the morning and become not only moody and irritable in the daytime, but find it difficult to focus in school too.

So, reducing exposure to the blue light of screens in the hours before bedtime is important for avoiding these problems.

Macular degeneration

Macular degeneration, also known as age-related macular degeneration, occurs when the cells in a small central portion of the retina – the macula – degenerate, usually in the elderly. This, in turn, causes deterioration of vision and may lead to blindness. Research shows that excessive and prolonged blue light exposure can damage the light-sensitive cells in the macula.

The bottom line?

At the end of the day, what is concerning about blue light is the amount of exposure. And as parents, managing and moderating your children’s daily exposure to the blue light emitted from their screens is key to giving their eyes adequate protection.

How should you go about doing this?

Protecting against the harmful effects of blue light with a reliable management system

It is obviously challenging to police your children’s exposure to artificial blue light all the time. Fortunately, the planoApp is a fuss-free tool that empowers your children to use their devices in a safe and healthy way so that you don’t have to.

To avoid long periods of blue light exposure, you can use the planoApp to schedule no-device-use times. For instance, scheduling device-free times in the planoApp for the hours leading up to bedtime will ensure that your children’s eyes get the break they need and that melatonin levels remain at the required levels to help them to sleep.

It is also advised that the blue light filter is activated on their digital devices during nighttime hours to reduce the harshness of the light entering their eyes before bedtime.

By helping to reduce your child’s exposure to blue light you lower their risk of eye strain and other vision conditions. Your children only have one pair of eyes, let’s help protect them!


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