Last week we discussed how by looking at a screen for too long and too often, we are harming our health in many ways. Since there is so much to the effects of the TV, computer or smartphone screen and the influence it has had on us, not all useful points can be discussed in one article. Therefore this week again we are going to see the ways in which computer screens and the light it emits affect our eyesight.

This effect on our eyes is very important for us to be aware of because it can sometimes takes years for the real effects on our eyes to actually become problematic enough for us to take note of. However, by that time it is too late to make amends, so we need to watch out right now to be able to see clearly in the future.

Everyone today spends a lot of time in front of the screen, and most of it is a computer screen of some sort, that is putting a lot of strain on the eyes. Too much screen time leads to digital eyestrain, leading to burring, itchy and tired eyes. Among the other physical symptoms that result from spending too much time in front of a computer/tablet/smartphone screen are headaches, fatigue, blurred or double vision, loss of focus, and head and neck pain.

Electronic devices also give off high-energy, short-wavelength blue and violet light. Early research shows that overexposure to blue light can contribute to eyestrain and discomfort.

Dr Tina McCarty, of the American Optometric Association, warns, “Blue light is very near ultraviolet light in wavelength and energy, therefore there is concern for cumulative damage over a lifetime of exposure.”

This blue light can affect vision and cause premature aging of the eyes, trigger serious conditions later in life such as age-related macular degeneration, which can lead to blindness. Thus she suggests, “A lifetime of protection is critical in protecting from certain eye-related disease as we age.”

While it’s still unclear how much blue light is too much, it is best to take preventive measures to limit children’s exposure to blue light from these devices. And the good news is that, “The eyes will get better when you give them a break and/or wear the proper eyewear in the form of lenses and coatings based on the patient’s specific needs to minimize eyestrain,” Dr McCarty explains.

The eyes in young people have the ability to accommodate and focus on close objects as the natural lens of the eye is smaller and clearer. But this is bad news as the blue light from a TV or computer screen gets more easily transmitted to the retina and is most likely to cause damage that may become obvious in the long run.

When looking at a screen, our eyes are forced to focus and strain a lot more than when doing other tasks. Computer usage demands fine motor skills from young eyes that are still not well developed, so it puts children at an even greater risk than adults for developing symptoms of computer vision syndrome. Only when the visual system matures is a person better able to handle the stress of a computer on that system. So we need to realise that there is much more strain on young eyes than on the eyes of an adult when watching a screen.

It is also seen that children don’t notice their vision problems when it starts, they simply assume that what they are seeing is the normal way to see things. Therefore, adults need to keep a closer check on children and make sure they have regular eye checkups, especially when they use screens too much.

Research has also shown that excessive smartphone usage may lead to a rare form of strabismus, or “crossed-eyes, “known as acute acquired comitant esotropia (AACE).” Although a very rare condition, in AACE “the magnitude of the eye turn is always the same, regardless of which direction the affected person is looking.”

A large study, conducted by the National Eye Institute and reported in 2009, found that the prevalence of nearsightedness among Americans has increased from 25 percent to 41.6 percent of the population over the past 30 years. Also, among people with 12 or more years of formal education, the prevalence of myopia is now as high as 59.8 percent.

Tips to protect the eyes

• Follow the 20-20-20 rule. Take a 20-second break every 20 minutes and look at something 20 feet away. As so far there is not standard for how much digital usage is safe for the eyes, taking breaks is the best way to protect your eyes.

• Children should also have eye examination each year as their eyes are still developing between the ages of five and 13.

• Reduce the amount of lighting in the room to match the computer screen. To reduce glare, windows and other light sources should not be directly visible when sitting in front of the monitor.

• The position and distance of a screen in relation to the user is important to prevent strain on the eyes as well as other parts of the body, such as back, neck, shoulders, etc.

• The computer workstation should be adjusted according to the body size of children. The recommended distance between the monitor and the eye for children is 18 to 28 inches. Viewing the computer screen closer than 18 inches can strain the eyes.

• Consult an eye specialist and find out about photochromic lenses or anti-reflective coating on power lens (if you already wear spectacles). These light-filtering computer glasses protect the eyes from blue light and visual fatigue. But only use it after recommendation by an ophthalmologist or eye doctor. — AK

Published in Dawn, Young World September 30th, 2017