What is Blue Light? And How Does It Affect Our Eye Health?

By: Dr. Rudy Gehrman.

You’ve surely heard the saying “the eyes are the windows to the soul”, but did you know that our eyes can also give us a view into our health? Through innovation in science and technology, we know that our eye health can tell us a lot about overall health. The health of our eyes is closely related to our balance, our sleep, and how our brain processes the world around us.

Our vision serves as the main source of information for us from the moment we first open our eyes as newborns. Our vision grows with our brains throughout our lives, progressing and regressing. It’s much more comfortable to talk about how our bodies progress, but let’s spend a moment on regression and explore how our current screen time habits can be contributing to this.

Understanding blue light is a good starting point. A great way to start to understand blue light is to take it back to elementary school and talk about the colors of the rainbow. Sunlight contains red, orange, yellow, green, and blue light rays and many shades of each of these colors, depending on the energy and wavelength of the individual rays. Combined, this spectrum of colored light rays creates what we call white light or sunlight. ROYGBIV or Roy G. Biv is an acronym for the sequence of hues commonly described as making up this rainbow of colors: red, orange, yellow, green, blue, indigo and violet.

Each of these colors affect us differently and even the same color, depending on source and distance from the eye, can affect us differently. When naturally occurring, blue light increases attention, reaction times, and mood. Nice! However, our association with blue light in our technologically advanced age has mostly detrimental effects. The artificial blue light we’ve come to know, including fluorescent and LED lighting, televisions, computers, and smartphones, sometimes referred to as “Alien Suns” can have harmful effects. This blue light penetrates all the way to the back of the eye and too much light will damage the retina, potentially leading to macular degeneration/blurred vision. This is worse on children’s eyes, which are more susceptible to the ill effects of blue light at fixed short distances, showing potential for delayed brain development. Yikes!

We are starting to see (pun intended) the negative effects first hand from constant exposure to blue light. So, what can we do about it? Essentially, we need to adjust how we are interacting with artificial blue light. But, how do we do that? Lucky for you, this is the part where I’m going to give you some action items to help you take your health into your own hands!

Brightness and distance from screens, as well as regular screen breaks, can help protect your eyes in a world where looking at screens is inevitable. Let’s start with brightness. Adjusting your monitor’s brightness to match your surrounding workspace brightness. When looking at the white background of your illuminated screen, if it looks like a light source in the room, it’s too bright. If it seems dull and gray, it’s probably too dark. Additionally, consider matte anti-blue light screen protectors, such as this one.

Next up is distance. We need to be cognizant of the distance between our eyes and our devices that we are reading from, as Myopia/nearsightedness can be a result of not being careful. To minimize this risk, make sure your screen is a least 25 inches from your eyes. You can also get into the habit of incorporating the ‘20-20-20 Vision Rule: take a screen break every 20 minutes, distance gaze at least 20 feet, and gaze for at least 20 seconds.

Once you’ve mastered these habits, consider incorporating print pushing, a concept taught to me by Avisha Nessaiver, my co-host at Biohack The World. The idea behind print pushing is to read right at the limit of your focal distance and to consistently push that distance to become farther and farther away. Print pushing is something you can incorporate into your normal routine while reading printed material or using digital screens. Making your eyes strain slightly during your regular activities, will help to keep it strong and prevent nearsightedness.

In addition to these daytime screen habits, rethinking how we spend our nights can be beneficial to our eye health. Our artificial sources of blue light are most disruptive at night. In addition to our overall screen use habits, our habits after the sun goes down—spending time in rooms with fluorescent lighting, staring into our phones late into the night, etc.—can be particularly damaging not only to our vision long term but to our sleep. Exposure to this artificial light that mimics sunlight once the sun goes down can mess with our circadian rhythm.

Okay, got it, but what is a circadian rhythm? It’s your 24-hour internal clock that is running in the background of your brain and cycles between sleepiness and alertness at regular intervals. It’s also known as your sleep/wake cycle. When the sun goes down, your pineal gland secretes the hormone melatonin, which tells your body to get tired and go to sleep. Blue light at night tricks your brain into thinking it is daytime and inhibits your production of melatonin, leading to a decrease in your quantity and quality of sleep.

To combat this, get in the habit of a good sleep hygiene protocol that fosters preventative eye health. When the sun goes down, minimize turning the Alien Sun on. Turn off your screens, dim your lights, and consider installing some red lights to navigate your cave before going to bed. You will sleep better, I promise. Dear night owls, it might seem impossible, but it is much healthier to get to bed early than to stay up late. Ideally, strive for waking up at sunrise after a good 8 hours of deep sleep. I’ll save your eyes now, in the spirit of good eye health, but will write another article regarding this claim in the future!

I know I’ve spent the last few paragraphs demonizing blue light but, some blue light exposure is essential for good health. As I mentioned previously, naturally occurring blue light is incredibly beneficial! Research has shown that this high-energy visible light boosts alertness, helps memory and cognitive function, and elevates mood. Artificial blue light when regulated can do the same. Blue light therapy has been used to treat Seasonal Affective Disorder (SAD), a type of depression that’s related to changes in seasons, and to regulate circadian rhythms.

While these habits are an essential way to protect our eye health, we can also work to fortify our eyes from the inside out. Studies funded by the National Institute of Health showed that a combination of Copper, Lutein, Vitamins C and E, Zeaxanthin, and Zinc benefit the retina. Eyecare supplements can be a valuable addition to your health routine! If you have any questions about health optimization, feel free to reach out to us by phone, or by filling out the form below:


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