Whenever your eyes meet light, whether it’s outdoors or flipping on a wall switch, they’re exposed to a lot of visible (and sometimes invisible) light.

Sunlight contains visible light rays and invisible ultraviolet rays that either tan or burn your skin. Furthermore, the visible light that’s produced by the sun comprises a variety of multi-colored rays that contain different amounts of energy.

Despite the fact that it’s environmentally friendly, blue light has several negative side effects. With the continuous development of our world, people once relied on the sun as their major source of lighting. Now, we have technology that not only gives us basic artificial lighting like the lamps, flashlights and overheard lighting – we now also have phones, tablets, and computers that illuminate our homes during the evenings.

This article will focus specifically on blue light and how it impacts us.

What is blue light?

In short, blue light is one color that makes up the visible light spectrum. As it’s a short wavelength, it produces higher amounts of energy. In contrast, red light has longer wavelengths and is made up of less energy. These two colors are on opposite sides of the visible light spectrum.

We are exposed to blue light when we browse our smartphones, watch television, and of course, when we are exposed to sunlight. With sunlight, it contains all colors of the visible spectrum and is called white light. Sunlight happens to be our largest source of blue light.

Is blue light bad?

Not all blue light is bad. In fact, blue light actually has many benefits. For instance, blue light during the daytime helps control circadian rhythms and provides small surges in alertness.

Moreover, as blue light is energy efficient, it is being used in more applications than ever before. The downside of this additional blue light exposure is it can disrupt natural sleeping patterns.

Blue light can also cause digital eyestrain, especially when you choose to use electronic screens for a significant amount of time. If you work in an office where working at a computer is required, do know that you’re at high risk of digital eyestrain.

Symptoms of digital eyestrain caused by blue light includes:

  • Headaches: This is a common symptom that is generated by too much stress on the eyes. If you already suffer from light sensitivity then you’re at higher risk of having frequent migraines from exposure to blue light.

  • Sore, itchy, red, or dry eyes: Dry eyes are the most common symptom. Staring at a screen for long periods can result in blinking less frequently than you should which causes your eyes to dry up.

  • Inability to focus: Due to eye strain and serious headaches, you’ll find it much more difficult to work on your computer or phone for long periods of time.

  • Sore neck and shoulders: If your eyes are constantly in pain or are uncomfortable it can result in additional tension and strain. The parts of your body that suffer from this the most is your neck and shoulders.

A solution to prevent digital eyestrain is to wear computer glasses with special lenses. These lenses are able to block blue light with wavelengths less than 450nm – so you’ll be able to view digital devices for longer periods of time.

When it comes to blue light, it isn’t just digital eyestrain you need to be careful of. There is a common side effect of blue light exposure called Retina Damage. Experts have concluded that continued exposure of blue light can lead to damaged retinal cells. Ultimately, being diagnosed with Retina Damage can cause vision problems such as age-related macular degeneration.

What about blue light is good? As mentioned before, blue light does have its benefits. Not only does it boost alertness, but it helps with your memory and elevates your mood.

You can even receive light therapy, which is performed to treat seasonal affective disorder (SAD) – a type of depression that’s sparked by the change in seasons. Symptoms can form during autumn and remain with you through the winter. The light sources for this therapy emit bright white light that has an abundance of HEV blue light rays.

Concerns of blue light exposure

As blue light has one of the shortest energy wavelengths in the light spectrum, it flickers more easily and longer than other types of wavelengths. This flickering forms a glare that reduces your visual contrast, impacting clarity and sharpness. Ultimately, this can cause eye strain and fatigue (both mentally and physically).

The reason why our eyes struggle with blue light exposure is that they are not evolved to provide filters against this type of light. Spending too much time focusing on this light can lead to devastating effects, including macular cellular damage, which can result in a loss of vision.

With macular degeneration, it is still unknown as to how much risk a person faces of developing this condition. There is a constant growth in usage of computers, smartphones, and other digital devices, that make it difficult to accurately measure. What eye care specialists are certain of is that this extra exposure to blue light isn’t good for your eyes and in particular your retina.

Doctors continue to be concerned by blue light exposure and the impact it has on us. According to Bluetech, here are some interesting statistics:

  • 43% of adults have a job that requires prolonged use of a tablet or computer
  • 74% of teens between the ages of 12 to 17 use electronic devices at least occasionally
  • 70% of adults that regularly use electronic devices report symptoms of digital eye strain
  • 93% of teens have access to or have a computer

Ways to decrease amount of time on blue light

Cutting down on blue light will help you sleep better, and it will avoid straining your eyes. Some ways to decrease the amount of blue light include:

Cutting down on your screen time. As we mentioned above, smartphones, tablets and laptops all emit blue light.

If cutting down on screen time isn’t an option, try to avoid blue light before bed because of the light’s impact on your body’s circadian rhythm. This is when your sleep can begin suffering. But the concerns don’t just stop there. Research has shown that this factor may contribute to major conditions like cancer, diabetes, heart disease, and obesity.

Use an app or program that filters blue light. The majority of modern cell phones contain blue light filters that are preinstalled. Check out the iPhone’s Night Shift or the Samsung Galaxy’s Blue Light Filter. With these apps, you’ll automatically adjust post sunset to limit the amount of blue light being released by turning to warmer colors.

If you happen to be on your computer during the evening, then there are apps for desktops and laptops you can take advantage of. If you are someone who relies on carrying out work during the night, then seriously consider downloading these types of apps. Many computers and devices come pre-loaded with these blue blocking features.

Purchase a pair of blue light-blocking glasses. They are growing in popularity, especially within today’s tech-driven society. This type of glasses can come as prescription or non-prescription and they contain special tinted lenses that decrease the amount of blue light being exposed to your eyes.

The 20-20-20 Rule

There happens to be a particular strategy that experts suggest using. It’s called the ‘20-20-20’ rule. With this rule, for every 20 minutes you spend looking at a screen, you should then focus your eyes on an object 20 feet away for 20 seconds. These consistent breaks will decrease the strain on your eyes.

How exactly does blue light impact sleep?

Everybody seems to have different circadian rhythms, but the average length is 24 and one-quarter hours. If you stay up late, then yours will be slightly longer, whereas it will be much shorter if you happen to go bed consistently early. A Harvard Medical School associate, named Dr. Charles Czeisler, concluded that daylight keeps a person’s internal clock aligned with the environment.

Light suppresses the secretion of melatonin, but blue light does so way more vigorously. According to health.harvard.edu, Harvard researchers and their colleagues conducted an experiment comparing the effects of 6.5 hours of exposure to blue light versus the same exposure to green light of comparable brightness. The blue light suppressed melatonin for about twice as long as the green light and shifted circadian rhythms by twice as much (3 hours vs. 1.5 hours).

Why our eyes are not good at blocking blue light

Our cornea and lens are incredibly effective at blocking UV rays from reaching the light-sensitive retina – which can be found at the backend of the eyeball. Less than one percent of UV radiation that comes from the sun reaches the retina – including when you’re wearing sunglasses.

However they are not structured to block out blue light. Virtually all visible blue light passes through the cornea and lens, which then touches the retina.

Have you had cataract surgery?

If you’ve been suffering with cataract and have had surgery, then protecting yourself from blue light is even more important.

You may find that once your cataract surgery has taken place, you’ll be given a pair of eyeglasses that contain lenses with a unique blue light filter – especially if you spend a large amount of your time on any form of digital device.


When it comes to blue light, anybody can be affected. It doesn’t matter if you’re a child, a teenager, an adult, or a senior – blue light can and will impact you. Today we are exposed to far more blue light than we were a few decades ago.

It’s important for your eye health to consider the ways that help prevent the suffering that blue light exposure can cause. Make sure not to underestimate the severe effects of blue light.