What is the "20-20-20 rule"? This simple remedy can help to ease the discomfort of digital eye strain. We live in a digital age, spending a good number of hours each day looking at screens of one kind or another. During the COVID-19 pandemic, this has increased dramatically, with many people working from home, children doing remote schooling, and communication with family, friends, and work colleagues often taking place via screens rather than personal contact. We have meetings, celebrations, and lectures, even yoga and dance classes on digital platforms. The social, educational, and psychological impact has been far-reaching, and this phenomenon has had an effect on the eyes, too, with eye strain and discomfort on the rise.
Like any muscle in the body, the eye muscles become fatigued from continued use. Because the text on digital screens is not as sharp as on the printed page, the eyes need to work harder to focus. There is often glare or reflection from a computer screen, as well as less contrast between the images and the background. Viewing angles are different than with written material, and continual eye focus and movement can cause eye strain and fatigue. Added to this, the viewing distance may be incorrect, causing poor posture and resultant back, neck, or shoulder pain. For many people who wear glasses, the prescription may not be correct for an extended time staring at a screen, and it may be necessary to adjust the prescription or wear glasses specifically for computer use. Humans normally blink around 15 times per minute, but this number is reduced by over half with lengthy periods staring at a screen, leading to dry irritated eyes.
Like adults, children are exposed to these risk factors after prolonged screen time, but they are more vulnerable than adults because their eyes are still developing. Young children often lie on their bellies while engaged with a phone or i-pad, placing strain on the eyes as well as the neck and back. While wrapped up in a favorite game or show, they tend to forget to blink and this has resulted in more strain on the eyes.
Although unlikely to cause permanent harm to the eyes, digital eye strain does cause uncomfortable symptoms including dry eyes, watery eyes, blurred or double vision, itching, burning, and eye fatigue. Other symptoms may include headaches, sore neck, shoulders, or back, and difficulty concentrating on the task at hand.
The 20-20-20 rule is one of the numerous techniques to alleviate the discomfort of digital eye strain. When using a screen, look away at something 20 feet (6m) away for 20 seconds every 20 minutes. The distance of 20 feet is unlikely to be exactly accurate, but this is not the key. The aim is to allow the eyes to focus further away than the screen so that they can refocus and rest. It takes 20 seconds for the eyes to relax completely. Although not always possible, even better than simply moving the eyes away would be to get up, take a short walk, do something unrelated to a screen. Drink a glass of water to hydrate the body or a cup of green tea which contains antioxidants that are beneficial for the health of the eyes. Any break from continual screen use, no matter how short, is beneficial.
Other ways to avoid eye strain include sitting at the correct distance from the screen, with the screen slightly below eye level. Adjust contrast, brightness, and font size on the screen, and reduce glare from overhead lighting or nearby windows. Grubby screens with fingerprints or dust increase eye strain, so make sure the screen is clean. If the eyes feel dry or gritty, have a humidifier in the room or use lubricating eye drops. Your optometrist can recommend appropriate artificial tears. Don't forget to blink! Contact lenses may exacerbate the problem, so give your eyes a break by wearing glasses from time to time. Ensure that your posture is correct and comfortable. If you wear glasses, check with your optometrist that your prescription is correct for computer work and, if necessary, discuss a pair of glasses specifically for this purpose.
It is important for parents or caregivers to check in with children regularly about how their eyes are feeling. They may be experiencing discomfort but be unable to recognize or describe it. Signs to alert adults to problems could be rubbing the eyes, squinting at the screen, blinking excessively when away from the screen, or complaints of headaches or tiredness. Screen time needs to be closely monitored and frequent breaks encouraged, preferably outdoors in natural light, allowing the eyes to focus on different distances and the body to exercise. As with adults, ensure good posture and make the necessary adjustments to the computer and the room in which it is being used. Remind the child to blink often. One expert has suggested allowing children to be bored by removing digital devices, which will spark and develop creativity and the opportunity for children to entertain themselves away from screens.