With so many of us spending hours glued to a computer screen, tablet or smartphone each day, it’s not surprising that we get asked this question time and time again. In short, the answer is ‘no’ – using a computer for long hours can cause eye strain but it is not harmful. Here we provide advice to relieve eye strain and improve comfort at the end of a long day.
Why do people develop it?
Eye strain is used to describe a range of symptoms from general tiredness, to blurred vision and discomfort of the eyes. It is usually caused by a combination of muscular fatigue (both inside and outside the eyes) and drying out of the eye surface. Research has shown that people blink less frequently and completely when using a computer. This causes the tears that protect the eye surface to evaporate more quickly leaving it exposed, and feeling gritty and dry.
How can I prevent eye strain?
You can reduce eye strain by making adjustments to your computer position and settings, and most importantly by taking regular breaks:
- Reduce glare from your computer screen – you can check this by turning your monitor off and observing bright light reflections on the screen. If needed, make adjustments to avoid your screen being directly behind or in front of a window, and reduce bright light sources using blinds or other means. Most newer screens include an anti-glare coating, but you can buy this as a separate attachment if needed. If you wear spectacles, keep in mind that there are a range of lens types, tints and coatings (including anti-reflection) that help reduce glare and eye strain.
- Check your screen distance – the closer the distance, the harder your eye muscles have to work for you to see clearly! A standard screen should be positioned 50-70cm from your eyes – this is roughly an arm’s length when you’re sitting back in your chair. You should also be looking slightly down at your screen – your eyes should be roughly level with the top of the screen when looking ahead.
- Adjust your screen display – the recommendations below are a rough guide so you may want to experiment to find the best combination for you:
- Text size – most people with healthy eyes use a text size of N10-N12. This is approximately 3x the smallest detail they can see at this viewing distance.
- Colour and contrast – the best colour combination for most people is black text on a white or a slightly yellow background. Research shows that bluer shades are more likely to cause eye strain.
- Brightness – your screen brightness should approximately equate the brightness of the area surrounding your screen for comfortable viewing. Hold a white piece of paper next to your screen and adjust the screen brightness to match the surfaces as closely as possible.
4. Take regular breaks – we cannot emphasise the important of this; keep reminding yourself until you form a habit! By taking breaks, you allow the muscles inside and outside of your eyes to relax, and give your eyes a chance to rehydrate. You can follow the 20:20:20 rule – every 20 minutes, change your eye focus by looking away from your screen and at something in the distance (approximately 20 feet or 6m away), for approximately 20 seconds. Remember to blink completely a few times to help the spread of protective tears across your eye surface. For every hour of work, take a 5-minute break away from your desk to stretch your legs and keep hydrated by drinking water. Whatever you do, try not to look at your phone during this time as it creates more work for your eyes. It is natural to forget to take breaks, but you can set reminders using a timer on your computer or smartphone, or by using apps designed for this purpose
How can I relieve eye strain?
Aside from taking a well-deserved break from your screen, there are options available to target the symptoms of dry eyes. These include using artificial tear drops or preparations, drinking more water and increasing the consumption of omega oils in your diet.
At the end of a long day, many people browse online using their phones or tablets. While this doesn’t harm their eyes, research has shown that exposure to bluer light shades can make it harder to fall asleep. If it’s difficult to avoid using these devices before bed, use their ‘night mode’ options to automatically adjust the background to warmer tones.