A £12 small LED torch that emits red light could vastly improve failing eyesight, a groundbreaking British study found.
Staring into its deep red light beam for three minutes a day for two weeks “significantly” improved participants’ vision, according to the first research of its kind in humans.
The discovery by researchers at University College London could signal the dawn of affordable home-based eye therapies, helping millions of people globally with ageing vision.
Welcoming the findings, lead author Professor Glen Jeffery, at UCL’s Institute of Ophthalmology, said: “Our study shows it is possible to significantly improve vision that has declined in aged individuals using simple brief exposures to light wavelengths that recharge the energy system that has declined in the retina cells, rather like recharging a battery.
“The technology is simple and very safe, using a deep red light of a specific wavelength, that is absorbed by mitochondria in the retina that supply energy for cellular function.”
There are about 12 million people aged over 65 in the UK, but this number will jump to around 20m in 50 years, all of whom will suffer some visual decline because of retinal ageing.
Mr Jeffery said: “As you age your visual system declines significantly, particularly once over 40.
“Your retinal sensitivity and your colour vision are both gradually undermined, and with an ageing population, this is an increasingly important issue.
“To try to stem or reverse this decline, we sought to reboot the retina’s ageing cells with short bursts of longwave light.”
In humans who are around 40 years old, cells in the eye’s retina begin to age. The pace of this ageing is partly caused when the cell’s mitochondria starts to decline.
The mitochondria are crucial to vision because they produce a type of energy called ATP to boost cell function.
Mitochondria are at their most dense in the retina’s photoreceptor cells, which have high energy demands.
The retina, therefore, ages faster than other organs, as it loses some 70 per cent of its energy source during a lifetime.
This leads to a major decline in eyesight, the researchers explained.
Building on their previous findings in mice, bumblebees and fruit flies, they finally turned to the human eye in their latest work.
By firing bursts of deep red, long wavelength light into human eyes, the performance of the retina’s light-absorbing photoreceptors improved considerably.
Mr Jeffery said: “Mitochondria have specific light absorbance characteristics influencing their performance: longer wavelengths spanning 650 to 1000nm are absorbed and improve mitochondrial performance to increase energy production.”
The retina’s photoreceptors mediate colour vision, provide peripheral vision and adapt vision in dim light conditions.
In the study, published in the Journals of Gerontology, the team recruited 12 men and 12 women, aged between 28 and 72, who did not suffer from eye disease.
At the start of the study all participants’ eyes were tested for the sensitivity of their photoreceptor rods, which deal with low light vision, and cones, which adapt the eyes to brighter light.
The recruits were then given a small LED torch to take home and were asked to look into its deep red 670nm light beam for three minutes a day for two weeks.
They were then re-tested for their rod and cone sensitivity.
Researchers found the light had no impact in younger individuals.
However, it “significantly improved” light sensitivity in those around 40 years and over.
The ability to detect colours improved by up to one-fifth in some participants in the 40-plus category.
This was especially the case in the blue spectrum which is more vulnerable to ageing.
Vision in low light, or “rod sensitivity”, also improved significantly for those of a similar age.
However, the progress was less notable compared to the boosts in colour detection.
Why are you making commenting on The Herald only available to subscribers?
It should have been a safe space for informed debate, somewhere for readers to discuss issues around the biggest stories of the day, but all too often the below the line comments on most websites have become bogged down by off-topic discussions and abuse.
heraldscotland.com is tackling this problem by allowing only subscribers to comment.
We are doing this to improve the experience for our loyal readers and we believe it will reduce the ability of trolls and troublemakers, who occasionally find their way onto our site, to abuse our journalists and readers. We also hope it will help the comments section fulfil its promise as a part of Scotland's conversation with itself.
We are lucky at The Herald. We are read by an informed, educated readership who can add their knowledge and insights to our stories.
That is invaluable.
We are making the subscriber-only change to support our valued readers, who tell us they don't want the site cluttered up with irrelevant comments, untruths and abuse.
In the past, the journalist’s job was to collect and distribute information to the audience. Technology means that readers can shape a discussion. We look forward to hearing from you on heraldscotland.com
Comments & Moderation
Readers’ comments: You are personally liable for the content of any comments you upload to this website, so please act responsibly. We do not pre-moderate or monitor readers’ comments appearing on our websites, but we do post-moderate in response to complaints we receive or otherwise when a potential problem comes to our attention. You can make a complaint by using the ‘report this post’ link . We may then apply our discretion under the user terms to amend or delete comments.
Post moderation is undertaken full-time 9am-6pm on weekdays, and on a part-time basis outwith those hours.
Read the rules here