Spending hours looking at a computer or phone screen has become inescapable in many workplaces: More than 104 million Americans are exposed to excessive screen time — defined as seven or more hours per day — including about 70% of people who have an office job, according to a report released in January by the American Optometric Association, or AOA, and the Deloitte Economics Institute that surveyed 1,000 people. 

Even as few as two hours daily on a device can cause eye problems, says Dr. Steven Reed, an optometrist and president of the AOA.

Unmanaged screen use can lead to issues including dry eye, eye strain, back and neck pain, headaches, heavy eyelids, tearing and blurred vision. The habit can also lead to increased visits to the doctor and decreased work productivity, the AOA report said.

Unplugging isn't always feasible, but there are steps you can take to protect your eyes from devices, doctors say. Here's how:

Adjust your work setup

Your eyes may thank you if you set up an ergonomic workstation. 

A lot of people have their computer screens positioned too high. Yours should sit slightly below your line of sight so you don't have to raise your head, Reed advises. Having your head in the wrong position can cause symptoms like neck pain and headaches, he adds.

You should also move your computer screen to an arms-length away and pull your smartphone farther away from your eyes, recommends Dr. Valerie Sheety-Pilon, an optometrist and vice president of clinical and medical affairs at insurance company VSP Vision Care. Modify brightness to a comfortable level depending on surrounding lighting and increase contrast on your device to reduce glare.

Getting glasses that block blue light and reflective light, which are available for prescription and non-prescription lenses, can be an effective option for some people to prevent eye strain, too, eye doctors say.

Practice the 20-20-20 rule

Take a brief break regularly to do the following exercise, called the 20-20-20 rule: About every 20 minutes, look up from your screen at an object at least 20 feet away for 20 seconds.

"When you're focused on anything up close, the muscles inside the eyes that help you focus … can get tired," Reed says. "When you look up at something further than 20 feet, those muscles tend to relax. You're giving them options to relax."

Consider your screen time after work

Outside the workplace, avoid using devices up to an hour or two before bedtime to improve your quality of sleep, Reed says.

"If you're on your screen until bedtime and then you don't really sleep well, that impacts your overall health significantly," he says.

See the eye doctor

Getting an annual eye exam is important even if you feel like your vision is fine, Reed says. Doctors can find and treat less visible conditions before they get worse.

When looking at a computer screen, it's a reflex to not blink as much, for instance, which can give rise to dry eye, Reed explains. 

You can speak to your eye doctor about whether artificial tears or rewetting drops are appropriate options to keep your eyes moist, Sheety-Pilon says.

An eye exam can also turn up other health problems that affect the rest of your body.

"Many people don't realize that an eye doctor can detect signs of more than 270 health conditions, like diabetes and high blood pressure, during an eye exam," Sheety-Pilon says.

She also notes that patients experiencing eye strain often need a prescription update or adjustment to their current glasses or contacts. 

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