You’ve got a headache for the third time this week, and the culprit could be anything: stress, a migraine, a burgeoning cold, or any of a hundred other things you’ve found on WebMD. But what if the pain is just coming from eye strain?
What causes eye strain
The Vision Council says that more than 60 percent of people report symptoms of digital eye strain, including headaches, neck and shoulder pain, dry eyes, and blurred vision. But what is it about those screens that causes strain in the first place?
“Your eyes are relaxed when viewing object that are over 3 meters away,” says Michael J. Duerr, an optometrist in Rochester Hills, Michigan. “Anything closer than that, the eyes are working.” When you’re peering at an object that’s closer to you, your orbs need to turn inward, or “converge,” and focus on that thing.
“Holding this posture for long periods of time can cause the muscles and eyes to strain,” says Duerr. Imagine holding a squat for hours—your muscles would get unbearably sore. When you’re focused on nearby sights, the same thing is happening to your eyeballs.
On top of that, keeping that focused posture means we often forget to blink. “Humans blink about 15 times a minute, but studies show we blink half to a third of that while using computers and other digital screen devices,” says Purnima S. Patel, M.D., clinical spokesperson for the American Academy of Ophthalmology. And when you forget to blink, your eyes feel dry. One study even suggests that blinking may allow your brain to rest briefly, so you can focus more after each dip.
It isn’t just screens that tire out your orbs: “Extended reading, writing, or other intensive ‘near work’ can also cause eye strain,” Patel says. However, recent research shows that screens cause higher rates of eye strain and irritation than printed text.
So if you’re focusing intently on text or other close-quarters work for a long period of time—as most of us do every day in the digital age—you’re giving your eyes quite a workout. Hence that pesky headache.
How do you know if it’s actually eye strain
So what separates an eye-strain headache from something more run-of-the-mill? You can’t pin it down by its location. “The feeling of a headache behind the eye may seem like it is coming from inside the head, from the sinuses, or from the back of the eye itself,” Patel says. “A headache behind the eye may or may not throb with your pulse. Where you feel pain is not necessarily an indicator of what’s causing the pain.”
Even if the headache is right around your eyes, that isn’t always a surefire sign that you can blame eye strain. “Headache behind the eye may be associated with a migraine, and can be similar to pain around the eye, behind the eye, or in the eye," she says.
A better way to figure out your pain’s cause is to try tracking the timing of your headaches. If you find those symptoms happen more often on workdays than weekends, or when you’ve been spending lots of time reading screens, there’s a good chance it’s related to eye strain.
Ultimately, though, there’s only one way to know for sure: “If you have a consistent headache and suspect it may be related to your eyes or vision, see an ophthalmologist,” says Patel. A professional can determine whether your symptoms are due to eye strain, or whether you need to see a different specialist.
If you don’t already have glasses, you may be surprised to hear that the American Optometric Association recommends getting an eye exam at least every two years. If it’s been a while since you visited an eye doctor, it’s probably time for another checkup—you may need glasses and not even know it, which could be contributing to your eye strain.
Your vision insurance plan should cover part, if not all, of an annual checkup. So as long as you make sure your local optometrist accepts your insurance, you have nothing to lose but an hour or two of your time.
Prevent eye strain
If you’re experiencing eye strain headaches, go ahead and take a couple ibuprofen or acetaminophen. However, you're better off taking measures to stop them from happening again. So go ahead and check out our guide to preventing eye strain.
Written by Whitson Gordon for Popular Science and legally licensed through the Matcha publisher network. Please direct all licensing questions to firstname.lastname@example.org.