How Does the 20-20-20 Rule Prevent Eye Strain?



Screen time is a big issue these days. You probably spend a good number of hours looking at screens, like your computer at work and at home, your smartphone, television, or other digital devices. Looking at screens too much can lead to eye strain. But the 20-20-20 rule may help.

Keep reading to learn more about this eye exercise, how to do it, and whether or not research says it’s effective.

What’s the 20-20-20 rule?

If you find yourself gazing at screens all day, your eye doctor may have mentioned this rule to you. Basically, every 20 minutes spent using a screen, you should try to look away at something that is 20 feet away from you for a total of 20 seconds.

How can you tell if something is 20 feet away?

Unless you have a tape measure you probably won’t be able to accurately measure 20 feet. Being exact isn’t the key. You should just try to focus on something far away from you. Consider looking out a window at an object that seems far away, like a tree or a building across the street. If you work in a small space, try walking outdoors or into a larger area where you can rest your eyes.

Why 20 seconds?

It takes about 20 seconds for your eyes to completely relax.

While you’re resting your eyes, it’s also a good idea to get up and grab a drink of water to keep yourself hydrated. If your body is hydrated, your eyes will be as well.

Drinking green tea during your break may help even more. That’s because green tea contains antioxidants called catechins that may help your eyes produce tears for better lubrication.

What about reminding yourself to do this every 20 minutes?

You probably get absorbed in reading or work when you’re looking at screens. Setting a timed reminder to pop up can help you take a break every 20 minutes. There are also free apps like Eye Care 20 20 20 that can help. Just click start when you begin your screen time, and the app will remind you to take a break.

What does the research say?

The American Academy of Ophthalmology explains that looking at digital devices won’t necessarily damage your eyesight. But it can cause strain and unpleasant symptoms. Humans normally blink around 15 times each minute. When staring at screens, this number decreases to a half or third that often. That can lead to dry, irritated, and tired eyes.

Eye strain caused by screens has its own name. It’s called computer vision syndrome (CVS). In a study, researchers examined computer use and its effects on the eyes of university students in Malaysia. Almost 90 percent of the 795 students had symptoms of CVS after just two continuous hours of computer usage.

Taking frequent breaks to look at faraway objects during screen time significantly lessened their eye strain symptoms. In other words, the 20-20-20 rule works.

While many doctors suggest the 20-20-20 rule is a best line of defense, researchers explain that any break from repetitive computer work or screens is beneficial. They also explain that children don’t typically notice eye strain as much as adults. As a result, children’s screen time should be monitored closely by caregivers.

This post originally appeared on Health Line.