If you’ve been hearing a lot about blue light exposure lately, there’s a very good reason. Scientists and doctors have been studying this particular wavelength of light for the past few decades, and what they’ve discovered is deeply concerning.
What Is Blue Light?
For humans, the visible spectrum of light ranges from red to violet. The longer wavelengths appear to be red, while the shorter ones appear to be blue. The blue light that is most worrisome is the thin band more specifically called blue-violet light. Because of its very short wavelength, it produces a higher amount of energy.
Though blue light is naturally present in sunlight, it’s the growing pervasiveness of blue-light-emitting electronic devices that is causing a problem. According to a 2016 Nielsen poll, the average American spends almost 11 hours a day in front of a screen. Most likely you’re reading this on a screen right now.
Because of our ubiquitous screens, we’re being exposed to far more blue light than our ancestors ever were — and its effects are cumulative over time.
Some Blue Light Is Good
Blue light plays an important role in many of the basic functions of the human brain, including memory, emotion, alertness, and cognitive performance. Certain wavelengths of blue light are used to treat a number of different conditions. Phototherapy in the form of blue light is used to reduce elevated levels of bilirubin in the blood of newborns, help people who suffer from seasonal affective disorder, and treat skin conditions such as acne, rosacea, and psoriasis. Due to frequencies that can destroy bacteria, some hospitals are even using blue-violet light fixtures to sterilize rooms, reducing the risk of methicillin-resistant Staphylococcus aureus.
Too Much Blue Light Is Bad
If blue light occurs naturally — and can help treat numerous problematic health conditions — how could it possibly be bad? Well, it all comes down to two detrimental effects blue light can have on our bodies. Let’s take a closer look:
Blue Light Is Hard on Our Eyes
Blue light is known to contribute to digital eye strain because it scatters more easily than other wavelengths, making it difficult to focus. When you look at the screen of a blue-light-emitting device, your eyes have to work harder. The harder your eyes work, the more likely they are to become tired and strained. Children under the age of 14 who use electronic devices are at special risk, as their corneas have yet to fully develop. In fact, prolonged exposure to blue light is a contributing factor in the increased diagnoses of nearsightedness among children.
Far more concerning is the role blue light plays in macular degeneration. Our eyes produce a compound known as retinal, which is an essential part of vision. This compound is aggravated by blue light, inducing multiple chemical reactions. Some of these reactions generate toxic radicals that can destroy photoreceptor cells. Once these cells die, they’re gone forever. There is no treatment for macular degeneration — the condition eventually leads to blindness.
Blue Light Interferes With Our Circadian Rhythms
Because the main source of blue light in our environment is the sun, our bodies have evolved to respond to that light. For most of human history, blue light has signaled our brains to get up and moving — to be alert and awake. Conversely, its absence has signaled that we should be sleeping. However, now that we are surrounded by artificial sources of blue light, these signals are confused and our circadian rhythm is being thrown off.
Researchers have found that a disordered circadian rhythm is surprisingly detrimental to our overall health. Evidence suggests that desynchronized circadian rhythms may play an integral part in diabetes, obesity, depression, and various tumoral diseases.
What Can We Do?
No doubt this information is concerning to you as it is to me — and you may be wondering what you can do to diminish the harmful effects of blue light on your body. Here are some options:
- Install warmer lighting in your home by purchasing yellow-tinted light bulbs.
- Most current smartphones have a blue light filter installed. Check your settings for a way to enable it.
- When working on the computer, wear blue-light-filtering glasses or use a screen protector or app that does the same.
- If you wear glasses or contacts, ask your optometrist about lenses with HEV filters already built in.
Finally — and perhaps most importantly — reduce your screen time as much as possible, especially in the dark, when the energy from blue light is more focused, causing more damage to your retinas.
It’s impossible to escape blue light altogether as we get it naturally from the sun. However, you do want to limit your exposure to it from electronic screens as much as possible, just to be safe. Though the jury’s still out on just how harmful blue light is to our bodies, there is enough evidence to point to its role in eye strain, nearsightedness, macular degeneration, and out-of-phase circadian rhythms. So take care out there — your eyes will thank you.
Also by Liz: How Introverts Can Thrive In An Extroverted Office
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