Excessive screen time during Covid-19 is causing a rise in digital eye strain, Paraparaumu optometrist Graeme Bunker said.
And it was important parents kept an eye on the amount of screen time their children were having.
Research commissioned by Specsavers before Covid-19 restrictions came into effect revealed the majority of New Zealand office workers were already experiencing symptoms of digital eye strain, with an overwhelming eight out of 10 people claiming to have experienced at least one symptom of digital eye strain while at work.
But the recent restrictions had meant a lot of people had spent more time on screens using computers and smartphones constantly for work and pleasure.
"If you've been going from remote working or studying to a Zoom hangout with friends or family, to a marathon session of Netflix, your overall time spent in front of a screen may add up to 10 hours or more a day," Bunker said.
"Our eyes aren't meant to be fixed on a single object that long and it's likely to have a negative effect on our eye health."
Digital eye strain can cause dry or irritated eyes, lead to blurred vision, difficulty focusing, sensitivity to light, eye fatigue, headaches and difficulty reading small print.
"There are some really simple things that people can do to combat the effects of digital eye strain, from drinking more water and blinking more often, to giving your eyes a break by looking up from your screen regularly."
Bunker cautioned that increased time on digital devices and near work with screens can be even more concerning for children than adults.
"With many school children having participated in remote and flexible learning from home under levels 3 and 4, they may have become more reliant on laptops and tablets for online lessons and entertainment and, due to social distancing restrictions, have generally been spending more time indoors.
"I understand how strong the pull of digital screens is for children and I also know that the way children learn, and play, is drastically changing as technology becomes increasingly incorporated into everyday life, especially during recent restrictions.
"Vision and eye health can have a major impact on a child's development not just on their education but on sports and social interactions as well.
"Staring at screens and being indoors for extended periods of time can increase the risk of a child becoming short-sighted (myopic), meaning their eyes focus well on close objects, while more distant objects appear blurred.
"Throughout primary school, children's eyes are still developing so it's vitally important that children are getting up and moving about throughout the day — spending time playing outside or engaging in activities where their eyes are not fixed on something close to them.
"Parents need to be reducing the amount of time their children are spending on screens or reading."
Bunker's top tips to prevent and reduce digital eye strain:
1. Blink. Humans normally blink about 15 times a minute. Make a conscious effort to blink as often as possible. This keeps the surface of your eyes from drying out. You might even want to put a sticky note on your computer screen reminding you to blink often.
2. Drink lots of water. Your eyes also dry out when you're dehydrated so it's important to keep up your fluid intake when sitting in front of a screen all day.
3. Follow the 20-20-20 rule. Take regular breaks to give your eyes a rest: every 20 minutes shift your eyes to look at an object at least 20 metres away, for at least 20 seconds. The easiest way to do this is to look out your window at something outside.
4. Adjust brightness and contrast. If your screen glows brighter than your surroundings, your eyes have to work harder to see. Adjust your screen brightness to match the level of light around you. Also, try increasing the contrast on your screen to reduce eye strain.
5. Reduce the glare. The screens on today's digital devices often have a lot of glare. Try using a matte screen filter to cut glare or simply cover your windows to avoid outside light shining on your screen.
6. Adjust your position at the computer. When using a computer, you should be sitting about 60cm (about at arm's length) from the screen. Also, position the screen so your eyes gaze slightly downward, not straight ahead or up.