What exactly is blue light? Blue light is defined as the low wavelength/high energy end of the visible light spectrum. The wavelength of visible blue light is in closest proximity to that of nonvisible UV rays. For this reason, much has been made recently of the potential eye health risks imposed by blue light. Early research suggests that excessive screen time, and its subsequent exposure to blue light rays may cause changes in your macula, similar to those found in macular degeneration.
Although most people associate screens and technology with blue light, blue light is actually everywhere. Sources include fluorescent lights, LED lights, TVs, computer monitors, and most notably, the sun! Our blue light exposure from screens is much less in comparison to the amount of exposure from the sun. However, there is concern over the many hours we spend staring at those screens in close proximity to our eyes.
Some early studies have shown that overexposure to blue light causes changes to your retina similar to those found in patients with age related macular degeneration, however the verdict is still out on how it increases your chances for developing macular degeneration. Macular degeneration sounds scary. In fact, approximately 1 in 8 people over the age of 60 in the United States will develop some form of macular degeneration. Current and future generations may be a higher risk than previous ones due to the drastic increase in the use of handheld electronic devices. A dilated eye exam allows for close inspection of the health of your macula.
Exposure to blue light will not cause any immediate symptoms. The strain that you feel after viewing your computer, smartphone, or tablet is not damage, but rather digital eyestrain. When we view screens, especially for extended periods of time, we actually blink less without even realizing it. Less blinking means more dryness, which can be quite uncomfortable. Prolonged focus at a near distance can cause general eye fatigue. To combat this, doctors recommend you follow the 20/20/20 rule. For every 20 minutes of screen time, you should view something at least 20 feet away from you for 20 seconds (or more!). As always, artificial tear supplementation is also effective in treating dry, tired eyes.
A normal amount of blue light exposure has benefits. It elevates your alertness, boosts mood, increases reaction time, and helps to regulate your normal sleep/wake cycle. Excessive amounts of blue light can throw off these natural rhythms resulting in fatigue and sleep disturbances.
What can you do to protect yourself from blue light? Your regular prescription glasses can be treated with antireflective properties that can help block blue light from both natural sources, and technology. And as an added bonus, you can’t even tell that you have it! It doesn’t change the color of your lenses. You should also try to avoid too much screen time at bedtime to improve your sleep quality. Your device may have a nighttime setting to reduce the amount of blue light transmittance.
More studies are underway to determine how much danger blue light possesses. But for now, its fair to say that limiting this exposure is a prudent measure. If you have any questions regarding blue light, just ask your CECO doctor at your next eye exam!
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