Is blue light dangerous to our eyes?
The blue light is more and more talk about it.Because it is emitted by the ubiquitous screens. Are we really getting more and more exposed?
Does the blue light represent a real danger to the eyes?
Should we wear anti-blue glasses when we use the screens a lot? Responses from specialists.
Part of the spectral light can be dangerous for our retina . To protect ourselves from a part of the light emitted by our screens , glasses anti ” light blue ” were born. How useful are they?
What is Blue Light ?
The blue light is a part of the light spectrum, whose wavelengths lie between 380 and 500 nanometers .
It is emitted by the sun , but also by artificial light sources : LED bulbs and screens (tablets, televisions, computers, smartphones).
The potentially dangerous blue light represents only a small part of the total blue light. blue-violet wavelengths . “The specter of daylight or artificial light includes strips of color.Among them turquoise blue, good light for morale, and then blue-violet, light to which we are increasingly exposed” , Explains Dr. Petra Kunze, ophthalmologist in Paris.
Indeed, the energy reaching the retina in the case of blue – violet light is stronger than in the case of turquoise blue light. Particularly screens diffuse peaks of blue light called Visible High Energy Light (or HEV).
The Blue Light Hurt My Eyes
“It has been demonstrated on an in vitro model of age-related macular degeneration (AMD) that the wavelength most toxic to retinal cells is located around 415-455 nanometers,” explains Serge Picaud neurobiologist And Inserm Director at the Institute of Vision 1 . This phototoxic zone corresponds well to a blue-violet light in the spectrum of the rainbow.
Scientific research has concluded that prolonged exposure to blue light or artificial HEV light causes photochemical damage to the retina and the lens . “Several epidemiological studies have demonstrated that this blue light is indeed a risk factor for AMD, “ recalls Serge Picaud 2.3 . The involvement of blue light in the development of cataract is also suspected.
However, blue light can also have beneficial effects. It helps with our circadian rhythms (sleep / wake alternation) and our mood. This time, it is the turquoise blue light (around 490 nm) which allows to adjust our rhythms during a jet lag. The latter regulates the production of melatonin, our “sleep hormone” 4 .
Prevention thanks to anti-light blue glasses
“There is not really any protection possible, except to put filters between the sources of light and our eyes,” informs Dr. Petra Kunze. There are blue light filters for screens , but not very widespread.
In France, several brands recently offer “selective photoprotection” glasses , in other words glasses whose glasses have a filtering treatment. Their principle? Protect the eye from light wavelengths toxic to the retina. These glasses filter blue-violet light but allow blue turquoise light to pass , in order to preserve the beneficial effects of the latter on the vision and regulation of the internal biological clock. These glasses have a slight reflection, of course purple.
What about for the man in the present state of the work,” says Jean-Manuel Finot, optician 1 . “These glasses block a large part of the light among the wavelengths identified as toxic for the retina, so we can assume that there is a real protection of the retinal cells,” adds the neurobiologist Pr Serge Picaud.
Glasses Anti Blue Light : Who is Concerned?
“All people exposed to this blue-violet light more than 30 mn a day could benefit from these anti-blue light glasses ,” Dr. Kunze. you like to walk outside, it is very recommended,” adds the ophthalmologist. The specialist advises in addition to make cures of 3 months of supplements food for the eyes from 40 years (based on lutein, vitamin E, zinc, antioxidants …), to repair the phototraumatisms.
“If you have a family history of AMD or cataracts . It is very strongly advised to bring these blue anti- light glasses , “ said optician Jean-Manuel Finot. Beware, however, not all glasses are equal: the different models do not all filter the same percentage of toxic light.
There is no contraindication to wearing these glasses anti blue light . “The only limiting factor is that these glasses prevent the blue light from reaching the retina by reflecting it. Resulting in a residual reflection, unattractive to the taste of some,” emphasizes Jean-Manuel Finot. However, these eye protections should still make progress in the future. “We can hope for more protective glasses , ” says Professor Picaud whose team continues to work on this subject.
On the price side, it is necessary to count between 35 and 50 euros per glass for a pair of glasses filtering the blue light without correction, for the people of less than 40 years having no visual problem. An extra cost per lens will depend on your correction if you have corrective glasses.
And as another protection trail? “In the future, it would also be useful for all screens to have built-in filters. Just like light bulbs,” said ophthalmologist Dr. Petra Kunze. An effective way to protect the vision of the entire population, without the need to equip themselves with eyeglasses