If you find yourself gazing at screens all day, the 20-20-20 rule may help. Every 20 minutes spent using a screen, try to look away at something that is 20 feet away for a total of 20 seconds. This is how long it takes for your eyes to reset and relax.

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.

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

Unless you have a tape measure you probably won’t be able to accurately measure 20 feet. Being exact isn’t the key to the 20-20-20 rule for eyestrain.

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.

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 published by the Nepalese Journal of Ophthalmology, 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.

Having sore, tired, burning, or itching eyes are the main symptoms of eye strain.

Other symptoms include:

  • dry eyes
  • watery eyes
  • blurred vision
  • doubled vision
  • headaches
  • soreness in the neck, shoulders, or back
  • sensitivity to light
  • trouble concentrating
  • difficulty keeping eyes open

While these symptoms likely point to eye strain, it’s a good idea to report any changes in your vision or eye health to your doctor.

Eye strain from computers and other digital devices can be uncomfortable. The 20-20-20 rule may help you avoid eye strain along with decreasing your time spent looking at screens. Even if the strain feels severe it will likely not cause permanent damage to your vision. And your symptoms should subside once you rest your eyes.

Want to avoid eye strain? Whenever you sit down to look at a screen, remember to follow these ergonomic eye tips.

  • Sit farther away from your computer screen. A good rule is to be at least 25 inches, or roughly an arm’s length, away. While you’re at it, move the screen so you have to look slightly downward at the screen.
  • Consider using a matte screen filter to reduce your screen’s glare.
  • Try your best to remember to follow the 20-20-20 rule. Set a timer to remind you to look away every 20 minutes at an object that is about 20 feet away for a full 20 seconds.
  • Buy some artificial tears at your local drugstore to use when your eyes feel dry. A humidifier can also help.
  • Blink often to help replenish your eye’s own tears.
  • Dim your screen if it’s much brighter than the rest of the light in the area. You could also adjust the room lighting so the contrast is lessened.
  • Keep your screens clean. Dirty screens with fingerprints and other debris can strain your eyes even more.

If you wear contact lenses, you may experience worsened symptoms of dryness and irritation. Try giving your eyes a break from time to time by wearing glasses.

Avoid sleeping in contact lenses, even those that are marketed as “extended wear.” Also always wash your hands and follow other good hygiene when putting in or taking out your lenses.

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