Is Blue Light Bad For Your Eyes?
By Cody Miller, EvergreenHealth Staff Writer
Like many of us, you may have wondered if the time you spend staring at your cellphone or TV is actually damaging your eyes. You've maybe even heard something about how the blue light all of your screens emit is harming you.
Rachel Reinhardt, MD, with EvergreenHealth Eye Care, answers your frequently asked questions: is blue light harmful and are screens actually bad for our eyes? The answers may surprise you.
According to Dr. Reinhardt, the American Academy of Ophthalmology (AAO) has been trying to dispel many of the myths involving our eyes and screens for years. The biggest myth is that blue light itself is harmful to our eye health. While it is known that blue light exposure 30-60 minutes before going to bed can interfere with sleep, blue light in fact does not harm your eyes.
However, that doesn't mean staring at our cellphones or computer screens for extended periods of time doesn't cause discomfort in our eyes. That is true, but it's not just because of the blue light.
Interestingly, we receive more blue light exposure from the sun than any other light source. That's in part why the AAO also advises skipping glasses that claim to protect your eyes from blue light.
The discomfort you feel from looking at screens is part of the eye strain that occurs in both adults and children, typically when we're concentrating on a task. Whether you're gazing at a screen of some sort, a piece of paper, a book or a work of art, our eyes can get quite achy during constant, concentrated staring.
This temporary discomfort is caused by a chain of events that occur naturally in most people during concentrated staring:
- First, staring causes your blink rate to go down by about 70%
- The lower blink rate causes the tear film on your eyes to evaporate
- This dryness causes our eyes to ache and feel strained
Additionally, staring at a single distance for an extended period of time can overwork muscles within our eyes, which is why when you look away off into the distance, your vision might get blurry temporarily. This is not harmful, but it is a good reminder to look away every 20 minutes or so to give your eyes a rest.
Recent studies have suggested that a lot of concentrated staring at really short distances, like reading books or sitting close to the TV, can contribute to near-sightedness, especially in children. So, if you have a bookworm at home or one of your children likes to play video games up close to the TV, have them take breaks every 20 minutes using the "20-20-20" rule, which means every 20 minutes, shift your eyes to look at something at least 20 feet away for at least 20 seconds.
While it may not be the blue light that is causing your discomfort, children and adults should take breaks from concentrated staring about every 20 minutes. Look up and far away to give your eyes some rest. Artificial tears (eye drops) can also be helpful.