Is blue light damaging my eyes?

Since the UK has been in lockdown many of us are spending more time in front of a screen, posing the question as to whether we are causing further damage to our eyes.

There has been conflicting reports about whether blue light can cause damage and more specifically increase your chances of developing macular disease. 

So, we've looked at the science and answered some of your questions. 

What are the sources of blue light? 

Sunlight is the main source of blue light but it can also be emitted by artificial lights, TVs, computers and smartphone screens.

Does blue light play a role in causing macular disease?

This is a common question – the short answer is that we can’t say for sure, but it’s unlikely.

It’s true that exposure to blue light can damage retinal cells in the lab – but only cells in a dish, or animal eyes. That’s an important distinction because these experiments expose cells to intense blue light for much longer than would happen in real-world conditions. Inside the human eye, the lens filters a lot of the light before it reaches the light-sensitive cells of the retina, so the exposure is much less extreme.

A review of the evidence in 2016 concluded that exposure to low levels of visible blue light for days or weeks had no impact on eye health, and found no evidence of damage from longer-term exposure over months or years.

Despite this, companies with ‘blue-blocking’ lenses to sell continue to make claims that aren’t supported by the evidence. In 2015 Boots Opticians was fined £40,000 for claiming that ‘Boots Protect Plus Blue’ lenses would protect eyes from damage caused by blue light.

Aren’t we exposed to a lot more blue light these days?

It might well seem so, if you add up blue light from artificial lighting, TV, and computer and smartphone screens. But the levels of blue light from these devices are still well below the amount you’d be exposed to just by going outside on a sunny day.

Should I stop using my computer or tablet?

No – especially if, like many people with sight loss, you rely on devices like these to work, read and find your way around.

Of course, there may be other reasons you want to cut down on screen time. There’s some evidence that using bright screens just before bed – whatever the colour – can make it harder to fall asleep, and affect the quality of your sleep. And we know that spending too much time looking at books and screens close to your face, rather than further away, can cause eyestrain, dry eyes and headaches.

So is there any point blocking blue light?

People with macular conditions may find that blue-blocking lenses help to reduce glare, improve contrast and sharpen images without cutting out too much light. If you think these might help you, speak to a low vision service, local council’s sensory support team or resource centre. The Macular Society Advice and Information Service can help too – give them a call on 0300 3030 111.

If you have cataract surgery, you may be offered blue-blocking replacement lenses as there’s a theory that these could slow down the progression of AMD. But a review by the National Institute for Health and Care Excellence (NICE) concluded that there’s no convincing evidence for this and that more research is needed.