In today’s digital world, many of us have seen our time spent looking at a screen increase dramatically, especially during the COVID-19 pandemic. Because of this, more talk of “blue light” has entered mainstream media and its potential harm to our eyes. We all want to make sure that we are taking care of our eyes to prevent any future damage. So, what is blue light, and should you be investing in blue-light blocking glasses?
Q: What is blue light?
A: When we talk about “blue light” we are referring to high-frequency visible wavelength light, just before the ultraviolet spectrum.
Q: Will exposure to blue light from my computer screen cause me to develop eye disease later on in life?
A: Our eyes have been exposed to blue light for thousands of years, as it is emitted in large amounts by the sun. Overexposure to blue light, such as being outside without proper UV protection, can raise the risk of developing eye disease. However, blue light is emitted in small quantities from our devices and has never been proven to harm our eyes.
Q: Do I need to wear special blue-blocking glasses to improve my sleep?
A: Blue light does play a role in the body’s normal circadian rhythm, or sleep-wake cycle. Blue light suppresses the secretion of melatonin so that when the sun is up, we stay awake. When the sun goes down and the brain receives less blue light, melatonin can be released and we are able to go to sleep. However, artificially exposing our brains to blue light from our devices can interrupt this cycle. Therefore, it is important to discontinue or reduce screen time during the evening hours. You can even set your screen to shift its emittance to warmer, longer wavelengths using Nightshift on iPhone or f.Lux for desktop, thereby reducing the amount of shorter wavelength blue light emitted from the screen.
Q: Is blue light causing my eye strain and fatigue?
A: Blue light is not the sole culprit for your eye strain at the end of a long day of computer use. Digital eye strain can present in different ways. Some of the most common symptoms include dry eyes (tearing, burning, gritty feeling), blurry vision, headache, tired or heavy feeling of your eyes. The cause of these symptoms is two-fold. The first is that when we stare at a screen, we blink less. Studies have indicated that a normal human blink rate is about 15 blinks per minute. This blink rate can be cut in half whenever we are doing anything that requires our focused attention, such as computer work. The second is that the muscles in your eyes are working to keep the image of your computer in focus. Just like any muscle in the body, they will get fatigued. Imagine holding a 10-pound weight above your head all day!
Q: What can I do to reduce my symptoms of digital eye strain?
A: With so many of us now working from home because of the COVID-19 pandemic, screen use and break time have had an inverse relationship. Natural break times (i.e. in-person meetings, going out to lunch, conversing with coworkers) have been all but eliminated during these unprecedented times. Because of this, it is of vital importance to remember to take breaks throughout the day by incorporating the 20-20-20 rule. That means every 20 minutes take a 20-second break and look at something 20 feet away. This allows your eye muscles to relax and get the rest that they deserve. As mentioned earlier, we also do not blink as much when using our devices. Therefore, make sure to consciously blink during your breaks as well as use lubricating eye drops throughout the day. If you wear contact lenses, try wearing your glasses during your workday, as contact lenses can further dry out the eyes.
Q: Should I get blue-light blocking glasses?
A: If you wear glasses, we always recommended that the lenses have a good quality anti-reflective treatment to make vision more comfortable. You can choose the type of anti-reflective coating that will reflect and absorb a bit more of the blue light from your screen. Ask your optician to show you a demo of the lens treatment! However, this does not replace the need to do all the things mentioned above, like taking breaks, consciously blinking, and the use of artificial tears throughout the day.
Q: Should I be concerned that screen use is damaging my child’s eyes?
A: Distance learning and increased screen time for children is another concerning side effect of the COVID-19 pandemic. It is reassuring to know that there is no evidence that screen use harms children’s eyes. Many parents wonder how much screen use should be allowed for their children. Unfortunately, there is no clear-cut answer. However, research has suggested that kids who spend more time indoors and on screens have a higher rate of myopia (nearsightedness) versus those who spend more time outdoors. Therefore, it is important to encourage outdoor activity and reduced screen time beyond what is required for school. As a general guideline, the American Academy of Pediatrics recommends no screen use for kids until they are 2 years of age and no more than one hour of screen time for children ages 2 to 5.