No matter how hard we try to limit screen time for our children, it seems inevitable that they end up using digital devices. Whether it be at school while learning, at home, in the car, or at restaurants to keep them distracted. But why are experts and Doctors telling us to limit their use? Digital devices emit blue light, which is one of the shortest, highest- energy wavelengths known. Because our eyes cannot naturally filter this wavelength of light, it can cause harm if not blocked properly. Below you will find some useful information in regards to what blue light is, where we can find it, why it is harmful, and how we can prevent damage to our health.
What is blue light:
Like I mentioned above, blue light is in the visible spectrum between 380nm- 500nm. What that means is it is one of the shortest and highest- energy wavelengths. It lies in a different area of the light spectrum than UV. UV light is in the non- visible wavelength zone, where as, blue light is in the visible spectrum. Both can be harmful, but in different ways.
Where can we find blue light:
Blue light can be found everywhere! The major sources include, our sun, digital and electronic devices, LED lighting, and Fluorescent lighting. A fun and interesting fact is that blue light is what makes the sky look blue! The blue light that is emitted from our sun collides with the atmospheric molecules causing the blue light to scatter. Our bodies use this natural light to signify when it is time to go to sleep and when it is time to be awake.
Many of today’s digital and electronic devices (computers, tablets, televisions, and cell phones) use LED back- lit technology and their increasing popularity and use are exposing our eyes to more blue light for longer periods of time.
Why is blue light bad for our eyes?
Our eyes cannot naturally filter blue light from any source. When we are exposed to artificial blue light from our electronic devices, the high energy wavelengths create a glare that can cause eyestrain, tiredness, headaches, and dry eyes. Studies are also being conducted to confirm the notion that too much blue light exposure can contribute to macular degeneration and other retinal problems, leading to vision loss. In addition, high levels of blue light exposure can decrease the amount of melatonin we produce, disrupting our natural sleeping patterns.
Children have exposure to digital devices more than ever in history and because they have larger pupils and a clearer lens, they are more susceptible to the harm that is associated with blue- light.
How to protect the eyes from blue light exposure?
There are a few ways to help prevent the amount of blue light our children are exposed to.
Limit screen time. This can be a constant battle, but the less our children use digital device, the less exposure they will have to artificial blue light. Encourage children to spend more time outdoors, read books on print, and keep themselves busy with activities that do not include devices.
The 20-20-20 rule. If a child is on a digital device, I advise my patients to have them take a break every 20 minutes, look at something 20 feet away, for 20 seconds. This will help with eyestrain, aches and pains from poor posture, and better blink rates.
Blue light protect glasses. When wearing glasses that block blue light, it can help get a better nights sleep as well as combat eye strain.
Wear sunglasses when outdoors. The sun naturally emits blue light rays and the eyes must be protected from this source as well.