Optometrist Daniel Cornelius reveals worrying health dangers of staring at a screen all day

An optometrist has revealed what really happens to our eyes after staring at a screen for hours on end – as Australians increasingly spend more time in front of computers and TVs during coronavirus isolation.

Daniel Cornelius, a member of the Optometrists Board of Australia, detailed the alarming eye-health dangers of staring at the computer, laptop, smartphone and television – and why we should always take regular breaks using the ’20-20-20′ rule.

The partner optometrist of Clearly.com.au said staring at your screen for multiple hours can lead to eye strain, dry and irritated eyes, headaches and blurry vision.

‘This will cause an increased level of eyestrain to every human eye, even for eyes with perfect vision and no focus problems,’ he explained.

‘The eyestrain can also lead to headaches and blurry vision in the short term.’

For permanent long-term cases, he said you could potentially develop myopia, also known as short-sightedness.

Optometrist Daniel Cornelius (pictured) staring at your screen for extended periods of time can lead to eye strain, dry and irritated eyes, headaches and blurry vision

He said the most common warning sign associated with eyestrain would be a ‘sense of blurry distance vision when we change from near focus to longer distance focus’.

‘When you focus on “close-up” objects such as reading materials for extended periods of time without taking breaks, your eye’s muscles begin to “adapt” to that range of vision,’ Mr Cornelius said. 

‘This stresses the muscles to the point that the muscles go into a spasm and then have difficulty relaxing. When you look away, objects at longer distances may appear as a brief blurred image as you change from near-to-far or vice versa. That is often the first indication that your focus mechanism is not coping with the level of eyestrain.’

Mr Cornelius said explained that when we read a book, we naturally look away from the print far more often than when we stare at a screen.

‘The often-dynamic nature of content on screen tends to “capture” our vision more and this often results in us “staring” at a screen for extended periods of time without looking away and changing focus,’ Mr Cornelius said.

‘Although we are able to do this, it is certainly not a “natural” action for the human eye.’

To prevent getting eyestrain from the blue light in devices, Mr Cornelius advised the best thing do to is take regular breaks using the ’20-20-20′ rule

Mr Cornelius said you should sit at a distance of about one arm’s length from the screen as this will provide the most comfortable viewing distance.

‘Extended periods of focusing at closer distances (less than 40 cm) creates significantly more eyestrain and associated symptoms compared to maintaining focus at intermediate distances (more than 70cm),’ he said. 

To prevent getting eyestrain from the blue light in devices, Mr Cornelius advised taking regular breaks using the ’20-20-20′ rule.

‘Every 20 minutes, shift your eyes to look at an object at least 20 feet away for at least 20 seconds,’ he said.

He said staring at screens for too long can also interfere with our ‘natural blinking action’.

‘Regular blinking is an essential component of tear production and tear distribution in the eye. If we do not blink normally, our tear film will become unstable and this may cause a feeling of dryness and discomfort,’ he said.

He recommended using eye drops to refresh your eyes when they feel dry and limit your screen time in the two to three hours before you go to bed.