Skip to main content

No, blue light from your cell phone won’t make you blind

Does blue light really affect your sleep? We ask an expert
Rommel Canlas/Shutterstock

Forget cancer: That devilishly useful smartphone in your pocket is likely to blind you before killing you – at least, if the latest round of breathless hype is to be believed.

Relax. Neither is true, despite what you might read in the headlines.

A new study from the University of Toledo reveals the process by which blue light impacts the photoreceptors in our eyes and leads to age-related macular degeneration, an incurable eye disease that can cause a loss of central vision. The fact that blue light does this is hardly revelatory, the authors state plainly, despite the headlines.

“We are being exposed to blue light continuously, and the eye’s cornea and lens cannot block or reflect it,” wrote Ajith Karunarathne, assistant professor in the UT Department of Chemistry and Biochemistry, in a press release about 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.”

That’s right, he’s proposing a way to possibly prevent this problem: Alpha tocopherol, a molecule derived from Vitamin E, may prevent the cellular death everyone is fretting about. You wouldn’t know that to read the headlines, however:

“Smartphones speed up blindness,” writes U.S. News and World Report. No, that’s not what the study says (although the U of T’s press release does suggest this by using the word “speed” in their headline. I’m not sure why. “Cause” would have been far more accurate.)

“Your phone is blinding you, scientists warn,” the New York Post wrote in a typically breathless Postian headline. Not quite.

“Blue light from smartphones accelerates blindness,” frets High Snobiety. Again, that’s not the conclusion the scientists drew. It’s not accelerating blindness, it’s the potential cause for one form of macular degeneration that may lead to some loss of vision. (For what it’s worth, Daniel Pearson who wrote the Snobiety article is the “life editor,” who recently wrote about WTF hairstyles at the World Cup and the 13-year-old skateboard prodigy who won the X Games.)

Look, macular degeneration is a fact of life. Our eyes are wonderfully complex devices that aren’t built to last forever, which is why nearly all human beings need eyeglasses and experience some form of eye disease in their lives. Karunarathne’s study details exactly how that eye disease happens, and blue light is part of that. And given that cell phones and other mobile screens do give off blue light (among other colors), is he running off to pick up special polarized sunglasses? Has he tossed out his deadly iPhone before blindness robs him of his vision?

Hardly.

“When we’re in the dark, our pupils are dilated and can take a lot of light …. But when you have some ambient light in the room, that will help your pupils contract a little bit and that will reduce the amount of light entering, which may bring down the light entering below the threshold [for damage],” he told host Larry Mantle and myself during a segment on 89.3 KPCC radio yesterday afternoon.

Read that again. Karunarathne said that the actions of the pupil may be enough to prevent an egregious volume of blue light from reaching your eye, except for at night – when we now have blue light filters that should help you sleep better and may prevent your cell phone from robbing you of your sight. And part two of the press release includes a quote from another one of the study authors, Dr. John Payton, visiting assistant professor in the UT Department of Chemistry and Biochemistry: “Some cell phone companies are adding blue-light filters to the screens, and I think that is a good idea.”

That blue light filter is called Night Shift on your iPhone, Night Light on a Pixel, Comfort View on LG, and so on. Here’s how to turn it on and how to use it.

Still worried? Technology may have offered a way to put blue lights in front of us at the very worst time, and a solution to that problem in filters, but it also offers options that go even further. Consider Republic Wireless’s Relay, essentially a cell phone replacement for children that has no screen at all. Think of it as the anti-cell phone. And Light makes a phone that demand you use it as little as possible.

So don’t worry so much about light cooking your eyes — and spend your time cooking with light instead.

Jeremy Kaplan
As Editor in Chief, Jeremy Kaplan transformed Digital Trends from a niche publisher into one of the fastest growing…
No, the Journal app on your iPhone isn’t spying on you
Apple Journal app on an iPhone 15 Pro.

If you've spent any time on Facebook, TikTok, or any other social media site over the last couple of days, there's a chance you've seen people claiming that your iPhone is spying on you — specifically, with a feature called "Journaling Suggestions."

One post I stumbled across on Facebook made it sound rather frightening, warning me that the feature shares my FULL NAME and EXACTLY where I'm located to anyone nearby. The post told me to go and toggle the setting off immediately because it was "Very scary stuff!!"

Read more
You won’t believe how I improved my phone’s battery life
The back of the Samsung Galaxy S24 Ultra, resting against a post.

Galaxy S24 Ultra Andy Boxall / Digital Trends

Sorry for using that tired old clickbait headline, but in a roundabout way, it’s true. You genuinely won’t believe that I’m about to tell you something so headbangingly obvious about smartphone batteries.

Read more
Don’t update your Google Pixel phone — you might break it
A person holding the Google Pixel 8, showing the screen.

One of the reasons to buy a Google Pixel phone is to be first in line to receive software updates — from new Android versions to important security patches. Unfortunately, one of the latest updates from Google is breaking some Pixel phones.

Over the weekend, a Reddit user on the r/GooglePixel subreddit compiled a list of threads from nearly a dozen Pixel owners reporting issues with their phones after downloading the most recent January 2024 Google Play system update.

Read more