Blue light from smartphones and laptops can make us blind, according to study

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Wordley

• A new study has shown how blue light can cause macular
  degeneration — one of the leading causes of blindness.
• Blue light harms our vision by damaging the eye’s
  retina.
• The study found blue light turns a molecule in the eye
  into a cell-killing poison.
• It kills photoreceptor cells, which do not
  regenerate.
• Special sunglasses that filter blue light might hep,
  but specialists are undecided about how much good they actually
  do.

Staring at screens all day isn’t good for us — we know this. It
can cause eye strain, sometimes called computer vision syndrome, and
the light is so bright it can mimic sunlight, mess with our
hormones, and prevent us from feeling
sleepy.

The blue light tablets, smartphones, and laptops emit is so
bright we can see our screens on a sunny day. It’s not natural to
be looking at such intense light all day long, so it’s no wonder
research is starting to find how bad it is for us.

According to a new study, published in the journal Scientific
Reports, this blue light might speed up our chance of
becoming blind. Previous studies have shown how harmful blue
light is, but researchers from The University of Toledo have
shown the mechanism of how it can make molecules become “toxic.”

The team found that shining blue light on eye cells transforms
vital molecules into cell-killing poison — which can lead to
age-related macular degeneration, one of the biggest worldwide
causes of blindness.

“We are being exposed to blue light continuously, and the eye’s
cornea and lens cannot block or reflect it,” said Ajith
Karunarathne, assistant professor in the UT Department of
Chemistry and Biochemistry, and one of the authors of the study.

“It’s no secret that blue light harms our vision by damaging the
eye’s retina. Our experiments explain how this happens, and we
hope this leads to therapies that slow macular degeneration, such
as a new kind of eye drop.”

Macular degeneration occurs when photoreceptor cells in the
retina die. They do not regenerate, so “when they’re dead,
they’re dead for good,” said Kasun Ratnayake, a PhD student
researcher and another author of the study.

Retinal — a substance formed by oxidation of vitamin A — changes
and kills photoreceptor cells by dissolving some of their
membranes.

The team added retinal molecules to other body cells, like cancer
cells, heart cells, and neurons, and they also died when exposed
to blue light because of the retinal becoming poisonous. Without
the retinal, blue light had no effect on the other types of cell.

“No activity is sparked with green, yellow or red light,” said
Karunarathne. “The retinal-generated toxicity by blue light is
universal. It can kill any cell type.”

Normally, there’s a molecule in our eyes called alpha tocopherol,
which is a natural antioxidant, and it stops photoreceptor cells
from dying. But as we age, or our immune system takes a hit, we
lose the ability to fight against the toxic retinal attack — and
that’s when the damage occurs.

Karunarathne said you can use special sunglasses that filter both
UV and blue light to try and combat the effects, but experts are unsure whether they do
that much good.

You can also try and avoid smartphones and laptops when it’s dark
— something you should be doing anyway if you want to get a good night’s
sleep.

“Every year more than two million new cases of age-related
macular degeneration are reported in the United States,”
Karunarathne said. “We hope to find a way to protect the vision
of children growing up in a high-tech world.”