Blue light from our screens can speed up the development of blindness

The title of this article seems a touch counter-intuitive as I tap away on my laptop with my phone by my side and, for some apparent reason, Come Dine With Me on the TV, all beaming blue light into my retinas, but I digress.

A paper published in Scientific Reports sheds light (pun intended) on the exact mechanism by which the blue light emitted from our digital devices can harm our vision and actually speed up the development of blindness. Our retina use cells called photoreceptors to sense light which in turn signals to the brain, allowing us to make sense of the incoming light. They require a specific molecule called retinal to sense light and its this molecule that the blue light is really influencing.

Our retina use cells called photoreceptors to sense light which in turn signals to the brain, allowing us to make sense of the incoming light

This blindness is caused by an eye disease called macular degeneration where the photoreceptors in the retina die, hindering our ability to sense light and signal directly affecting our vision. This disease is common in the 50-60 age bracket, but this increased exposure to blue light could be causing this age of onset to fall rapidly. Dr Ajith Karunarathne, an assistant professor at the University of Toledo where the study took place said: “We are being exposed to blue light continuously and the eye’s cornea and lens cannot block or reflect it.”

The researchers at Toledo found that the blue light causes the retinal in the photoreceptors to trigger a cascade of reactions, resulting in the production of toxic molecules in the cells. This leads to cell death via dissolving a key signalling molecule on the cell membrane.”You need a continuous supply of retinal molecules if you want to see,” Said Kasun Ratnayake, a PhD student working on the study. “Photoreceptors are useless without retinal, which is produced in the eye.”

Researchers at Toledo found that the blue light causes the retinal in the photoreceptors to trigger a cascade of reactions, resulting in the production of toxic molecules in the cells

This increased exposure to blue light brought about by the digital age could be causing the early development of macular degeneration. Scientists in the lab in Toledo are measuring the blue light emitted from our plethora of digital devices to get an idea of how our eyes are responding to everyday exposure. “Photoreceptor cells do not regenerate in the eye. When they’re dead, they’re dead for good,” added Ratnayake.

This study begins to illuminate (pun intended again) the effects the digital world is having on the human body. Understanding the science behind this is the first step in us finding a way to protect our vision is future generations grow up in an increasingly technological world.