Children as young as five years old and high numbers of teenagers are going to optometrists with eye damage as a result of heavy digital device use.

A nationwide survey of New Zealand optometrists finds that 87 per cent of them are concerned about the number of people presenting with eye damage, some as young as five years old, according to a recent survey.

Optometrist Bruce Nichols is prescribing blue light filtering lenses. Photo: Supplied

The Eyezen study also shows that eight 80 per cent of optometrists believe the patients most affected are aged between 30 and 40 and disturbingly 19 per cent say teenagers are also in the highest risk group.

Dry eyes, eyestrain and headaches are the main symptoms. Other common symptoms are stinging/tired or itching eyes, discomfort caused by the glare of the screen, and a progressive difficulty in staring at the device.

'Strained vision, headaches and sleep deprivation are all linked to the high energy blue light emitted by flat screens and the cumulative effect of regularly switching between multiple devices,” says Optometrist Bruce Nicholls.

Many people are looking at phone screens up to 150 times a day along with additional exposure to laptops, tablets and PC's.

'What we are seeing now is that concentrated numbers of hours spent in intensive screen time while gaming and even long work days are causing noticeable symptoms in device users. Essentially over-exposure to that blue light - which occurs on the light spectrum next to harmful invisible ultraviolet light - could cause significant, long term damage.”

Also of concerning is recent research showing 90 per cent of technology users are working across multiple screens for everyday activities, again increasing their risk of harm from blue light.

'According to one study, 75 percent of people who use two or more devices simultaneously report experiencing symptoms of digital eye strain compared to only 53 percent of people who use just one device at a time,” says Bruce.

'There are strong suspicions that high energy blue light could cause damage to the macula, which could cause loss of central vision over a lifetime of use. That is what is now being researched globally.”

Nicholls says a better-safe-than-sorry approach needs to be adopted and advocates blue light protection as a counter to increased screen use for patients under 40.

'What we are saying to younger people who will potentially spend a huge proportion of their working life in front of blue-light emitting screens is that that could well be a problem for you. It's a cumulative problem,” says Bruce.

Multiple studies and articles also highlight the effect blue light has on the human body clock, with the impacts from the sleep deprivation caused by overexposure potentially including cancer, diabetes, heart disease, and obesity.

Tech companies like Apple have reacted to the flood of information about blue light by introducing technology it claims reduces the amount of blue light emitted by its smartphones and tablets, says Bruce.

He prescribes blue-light blocking lenses to increasing numbers of Kiwis displaying symptoms of digital eye strain.

'I usually prescribe it for people who have visual fatigue from prolonged screen use and it does make quite a bit of difference de-stressing their focus system - which is what it is designed to do.

'The pretext is that if you stop blue light from entering the eye then potentially you stop its damaging effects.”