Fair Go: Know before you shop for popular blue light blocking glasses

Blue lens, or blue light blocking lenses are all over social media, and are a celebrity favourite too.

Blue lens or blue light blocking glasses are becoming a popular buy for those looking to get some relief from spending time on their screens.

They're also a celebrity favourite, with stars like Drew Barrymore, Jennifer Lopez and Rashida Jones getting behind big name glasses brands in the US. Social media influencers are praising these blue light blocking products online, leading many to believe that blue light causes damage to the eyes, and that these glasses work to ease the tension that too much screen time can cause.

But what many people don't know is that the sun is our biggest source of blue light. It's more or less why the sky is blue. It's also essential for good health. It boosts alertness and helps our cognitive functions. It also keeps our body clock, or our circadian rhythm, in time with the natural day/night cycle.

So we do need blue light, but it turns out too much of it at the wrong time isn't good for us. The artificial blue light from our television, computer and phone screens at night can cause poor sleep. Research tells us there is a definite link between our exposure to blue light and our sleeping patterns.

When the cells in our eyes detect the brightness of the light around us, they tell the brain to get up and be active or to go to sleep. Blue light supresses the hormone melatonin - that's what we need to feel sleepy - and so our sleep patterns get disrupted.

And that disrupts everything else.

Daniel Ebbett created his own brand of blue light glasses, launching his business, Block Blue Light NZ, in 2016.

He used to work in the information technology industry and was used to working on his computer screens through the night.

"For so long I was having chronic sleep deprivation which in turn was causing a lot of just anxiety, depression, lots of health problems," Ebbett told Fair Go.

He credited his extended time on screens to his health issues, which motivated him to research the effects of the artificial blue light we get from our screens on the eyes.

"It's quite crazy - in today's world, it's almost like you can't escape it," he says.

"Even if we open our fridge to get some food, we just get blasted with blue light, then we're looking at our phones before bed, we're watching TV, we're on computer screens, so essentially we're just being, what I would say, as bathed in this type of artificial light."

Most of that artificial light is LED or light-emitting diodes, which emit more cool, blue light, than the older, warmer incandescent lighting that give off yellow, orange tones.

Ebbett created a pair of night-time red lens, blue blocking glasses to combat the amount of blue light he was taking in at night, which makes for an interesting look.

"In order to completely block out a colour of light, you need to oppose it with another colour so it can absorb the light as it comes through," he says.

"You might get some strange looks from people that come in to your home where things are lit up a bit yellow and you've got these red lenses on."

Pippa Wetzell with what to do if you want to reduce the effects of screens on your sleep, but don’t want to invest in glasses.

While not everyone's convinced, Ebbett swears by his blocking products crediting them with helping him get a good night's sleep.

But most people are familiar with the clear daytime lenses, which are now sold in local fashion retailers. These are the type that Fair Go put to the test.

Director of Auckland University's Bachelor of Optometry Programme, Dr Andrew Collins, says in general, clear lens, blue light blocking glasses are blocking "maybe between 10 and 30 per cent of the blue light, depending on the brand".

"Blue light is still getting through them, and that's actually important for day to day wear, because if you blocked all the blue light, you defect your colour vision."

Collins says, "It's important that the sort of perhaps day to day blue blocking glasses let through enough blue light to make your vision work normally".

But when it comes to eye strain, Collins says the research is inconclusive.

"Nobody has a clear idea of what the exact link would be between blue light and eye strain.

"If you're talking about eye strain through doing lots of near work, that could occur whether it's a computer or maybe doing embroidery, so it's the fact you're doing a lot of near work."

Fair Go tested a three pairs of glasses at three different price points: a $20 pair, a $30 pair, and a $115 pair. They were tested on an instrument called a spectroradiometer, which measures the energy of light coming off the screen. The way to think about it is if you think of the colours of a rainbow, and how much or how intense each of those components of each of those colours is.

The glasses were tested in a transmission test that shows how much blue light is being transmitted from a screen into the lens. The results are shown in a colour spectrum graph form, showing the full spectrum of visible colours from blue to red. If the reading of blue light is low, this means blue light is being blocked and vice versa if the reading of the blue light is high.

The $20 pair didn't block so much. The blue levels of light on the colour graph were still high.

The $30 blocked more than the $20 pair, but not that much more. The green and yellow levels increased on the graph, which meant the blue level was decreasing and so, was being blocked.

The $115 pair blocked the most blue light out of the three, and in Collins' words, were "performing better". So, price does matter if you're looking to invest in a pair of these glasses.

But Collins wants to remind people that no matter how much you pay for a pair, "if you ever do buy any of these types of glasses and you put them on and they make your eyes uncomfortable, that's immediately a sign that they're not gonna be good for you".

"You're not gonna cause any harm to yourself by wearing these lightly tinted lenses. If your eyes feel better, that's great, that works for you."

SHARE ME

More Stories