Staring at a deep red light for three minutes a day can significantly improve declining eyesight in people aged over 40 years, finds a new UK study, which is the first of its kind in humans.
Scientists believe the discovery, published in the Journals of Gerontology, could signal the dawn of new affordable home-based eye therapies to help people with naturally declining vision. At around 40 years, human retinal cell ageing accelerates, leading to vision deterioration.
Researchers built on their previous animal model studies, which found significant improvements in retinal photoreceptor function when eyes were exposed to 670 nm (long wavelength) deep red light.
For the study, 24 people (female/male, 12/12) aged between 28 and 72 years, who had no ocular disease, were recruited. All participants’ eyes were tested for the sensitivity of their rods and cones at the start of the study.
All participants were given a small light-emitting diode torch to look into its deep red 670 nm light beam for three minutes a day for two weeks. They were then re-tested for their rod and cone sensitivity.
Researchers found the 670 nm light had no effect in younger individuals, but in those around 40 years and over, significant improvements were obtained.
Cone colour contrast sensitivity improved by up to 20 per cent in some people aged around 40 years and over. Improvements were more significant in the blue part of the colour spectrum, which is more vulnerable in ageing.
Rod sensitivity (the ability to see in low light) also improved significantly in those aged around 40 years and over, though less than colour contrast.
Lead author Prof Glen Jeffery said: “Our study shows that 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 re-charging a battery.”