A small LED torch that emits deep red light and costs just £ 12 to make could help improve vision loss, scientists said.
A University College London study, involving a small sample of 24 people, found that looking at long-wavelength light for three minutes each day can “dramatically improve vision” in people 40 and older .
Scientists believe the discovery, published in the Journals of Gerontology, could pave the way for new affordable, patient-achievable eye therapies at home.
The cells of the eye retina start to deteriorate around the age of 40.
According to the researchers, the rhythm of this aging is due in part to a drop in the mitochondria of the cell, whose role is to produce energy and boost cell function.
Lead author Professor Glen Jeffery of the UCL Institute of Ophthalmology said: “As you get older, your visual system decreases dramatically, especially once over 40 years of age.
“Your retinal sensitivity and your color vision are both progressively weakened, and with an aging population, this is a growing problem.
“To try to stem or reverse this decline, we have sought to restart aging retinal cells with short bursts of longwave light.”
The researchers recruited 24 people, aged 28 to 72, who had no eye disease to participate in their study.
Participants were given special LED torches to take home and were asked to look into its deep red beam of 670 nm for three minutes a day for two weeks.
They were then retested for color vision as well as for low light vision.
The ability to detect colors has improved by up to 20% in some people aged around 40 and older, according to the researchers.
The ability to see in low light also improved significantly within the same age group, they added, although the improvements were not as dramatic as the gains seen in color vision.
The effect was not observed in younger individuals under the age of 40.
Professor Jeffery said, “Our study shows that it is possible to dramatically improve diminished vision in the elderly by using simple brief exposures to light wavelengths that recharge the energy system that has declined in retina cells, rather than recharging a battery.
“The technology is simple and very safe, using deep red light of a specific wavelength, which is absorbed by the mitochondria of the retina which provide energy for cellular function.
“Our devices cost around £ 12 to make, so the technology is very accessible to members of the public.”