Let's do a bit of science today!
We are going to talk about blue light, its effects on the eyes and the solutions I use to avoid being too exposed to it.
Blue light, what is it?
Blue light is a part of the visible light spectrum. Its wavelength is between 380 and 500 nanometers and it represents about a third of visible light.
The Sun emits this light in a natural way but it also could be emitted by artificial light sources such as LEDs, smartphones screen, computers screen or televisions.
The peculiarity of this light is that it is the most energetic light of the visible spectrum. The fact that it is very energetic makes it potentially dangerous.
We all know that we need to protect our eyes from UV rays, but what about blue light?
Blue light is made up of 2 parts:
-Blue-violet light between 380 and 455 nanometers, mainly between 415-455 nanometers which accelerates the aging of the retina.
-Blue-turquoise light 455 and 495 nanometers, which, on the other hand, is essential for our body. As a matter of fact, this light contributes to the balance of our biological rhythm by regulating the production of melatonin, the sleep hormone. It also has a positive effect on our mood.
The problem with blue light therefore comes from blue-violet light.
In 2020, French children aged from 6 to 12 years old spent an average of 7 hours a day in front of their screens, yes that's true !! The lock down having greatly accentuated this trend.
As for adults, they would have spent about 4 hours in front of the television, but this numbers do not include the time spent in front of the computer or smartphones, which obviously will making these numbers go way much higher!
Suffice to say that we are all exposed to this blue light for many hours a day and perhaps more than is necessary for the health of our eyes.
How does blue-violet light affect our eyes?
Blue-violet light emits energy that reaches the retina more strongly than turquoise blue light. Screens in particular emit peaks of blue light called High Visible Energy (HEV) light.
"It has been proven on an in vitro model of Age-Related Macular Degeneration (AMD) that the most toxic wavelength for retinal cells is around 415-455 nanometers ", tells us Professor Serge Picaud, neurobiologist and Inserm director at the "Institut de la Vision".
Scientific research has shown that prolonged exposure to blue light radiation or artificial HEV light causes photochemical damage to the retina and crystalline lens.
Several epidemiological studies have also shown that this blue light is indeed a risk factor for AMD.
Additionally, blue light could also be an aggravating factor in the development of cataracts.
How to protect our eyes?
In order to avoid the negative effects associated with blue light, I personally have been using for years free solutions and little technical tips .
I will share them with you!
First of all, for my computer I am using f.lux, you can download it here. It's a super handy little tool that adapts the brightness of your screen depending on the hour of the day. Depending on the time of day and your location, the software will automatically calculate the brightness which is best for your eyes.
You can also set it up however you want with the many colors available. I prefer the classic one which is my favorite in the end!
For Android phone users, f.lux is also available as an app that you can download from the Google Play Store. But I never tried it because I don't have an Android phone.
For others who have an iPhone like me, I couldn't find a good app. By the way, I'm a taker if you have one ;)
From my point of view the night mode doesn't really do a good job either, so I personalized the settings to limit the blue light on my phone screen.
In Settings go to Accessibility, then Display accomodations and Color filter as shown below. You can then choose the intensity and color you want!
In addition to all these preventive actions, I encourage you to practice Eye Yoga poses to limit the eye fatigue and maintain good eyesight! You can find some examples of these poses on my Instagram or Facebook account @faceyogananda.
Let's start today to better take care of our eyes!