A new study from the University of Toledo has revealed how blue light from smart devices and screens is damaging our eyes. The researchers strongly recommend avoiding looking at cellphones and tablets in the dark.
"We are being exposed to blue light continuously, and the eye's cornea and lens cannot block or reflect it," says Ajith Karunarathne, one of the researchers on the new study. Human vision relies on a molecule called retinal to sense light, and send visual information to the brain.
Immune system can't handle excessive exposure
"You need a continuous supply of retinal molecules if you want to see. Photoreceptors are useless without retinal, which is produced in the eye, explains Karunarathne. The recently published study found that when exposed to blue light retinal can turn against the body, generating the types of chemicals that destroy photoreceptor cells.
"It's toxic. If you shine blue light on retinal, the retinal kills photoreceptor cells as the signaling molecule on the membrane dissolves," says Kasun Rathnayake, another researcher working on the project. "Photoreceptor cells do not regenerate in the eye. When they're dead, they're dead for good."
The study discovered that age-related macular degeneration occurs when the body’s immune system is less able to protect itself against this combination of retinal and blue light. No other visible spectrums of light such as green, yellow or red triggered the same retinal process as blue light.
Vitamin E could help protect eyes
However, they did discover that a derivative of vitamin E called alpha-tocopherol can protect against this degenerative process. The study needs to now examine exactly how much blue light is emitting from tablets and screens to more accurately understand the consequences for people who use screens on a frequent basis
"If you look at the amount of light coming out of your cell phone, it's not great but it seems tolerable," says John Payton, who also worked on the study. "Some cell phone companies are adding blue-light filters to the screens, and I think that is a good idea."
Blue light accelerates natural aging process
Age-based macular degeneration occurs naturally even without the presence of screens as our eyes are exposed to blue light from sunlight. However, the discovery of the degenerative process resulting from the combination of retinal and blue light may show that the degeneration is sped up for those that use screens regularly.
While other studies have been done on how exposure to blue light affects mood as well as significantly disrupt our circadian rhythms, this is the first time that a study has looked specifically at how blue light can be detrimental to our eyes.
The new research was published in the journal Scientific Reports.
Via: University of Toledo