The Healthy Living Index Survey conducted with 10,316 adults across Asia in 2016 revealed that the average Singaporean spends about 3.7 hours online daily on non-work-related matters.

Another study in 2015 showed that Singapore millennials (aged 16 to 30) spend about 3.4 hours per day on their mobile phone, excluding hours clocked in front of the TV or a computer. This makes Singapore one of the most digitally-engaged countries in the region.

How Excessive Use of Digital Devices Impacts Our Health

Doctors warn that excessive use of digital devices can lead to a lack of sleep, change in diet, mood swings and other health problems such as body aches, carpal tunnel syndrome (a painful condition of the hand and fingers caused by continual repetitive movements) and Computer Vision Syndrome (CVS).

How Prolonged Computer Usage Affects Our Eye Health

Prolonged hours in front of devices can cause eye strain.

CVS is an eye condition related to prolonged and uninterrupted use of computers and digital devices. Symptoms include tired eyes, tearing, redness, and a dry sensation in the eyes.

“The eyes work harder when they read from a screen because screen images are made of pixels — tiny dots that have a bright centre and blurred edges,” explains Dr John Wong, Associate Consultant at the National Healthcare Group Eye Institute, Tan Tock Seng Hospital.

“As a result, our eyes constantly have to focus, relax and refocus to read the pixels — which tires out the muscles.” By comparison, printed images and words are solid and well defined, hence less visually demanding.

Dryness, A Cause of Eye Strain

Prolonged attention to the screen also means we blink less than we normally would. “A reduction in blink rate causes the eyes’ ocular surface (parts of the eyes that are bordered by the upper and lower lids) to be exposed more often. “This results in dryness which causes eye strain,” says Dr Wong.

In addition, we tend to open our eyes wider when staring at a screen than while doing other tasks. The extra exposed surface, as well as infrequent blinking, can accelerate tear evaporation and cause further strain.

Environmental factors also contribute to CVS. “Air conditioning, for example, makes the air in the environment drier, thus causing ocular discomfort,” says Dr Wong. “This can be made worse if you are seated directly against the direction of the draft from a fan or air-conditioner.” According to a June 2016 report by British newspaper The Guardian, CVS affects 70 million people worldwide.

Related: Keeping An Eye on Your Eye Health

Preventing Eye Strain and Permanent Damage to the Eyes

There are a number of ways to prevent eye strain.

The effects of prolonged computer use are not just vision-related. Complaints from those afflicted include neurological symptoms like chronic headaches and musculoskeletal problems such as neck and back pain. The good news is that the symptoms of CVS are temporary and can be resolved with rest. CVS can be prevented by practising “proper personal eye care” and through “environment modification”, says Dr Wong.

It is unwise, though, to ignore the symptoms of CVS. “Patients may develop more severe and prolonged symptoms if the initial ones are not properly managed, but these are unlikely to cause permanent damage to the eyes,” he says.

If symptoms are persistent after personal eye care, consult a doctor immediately. “A detailed examination by an ophthalmologist is needed to rule out other causes of blurring of vision and eye discomfort,” says Dr Wong.

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