A study has found that exposure to a certain wavelength of light for a short period can improve eyesight. This discovery, led by researchers from University College London, was recently published in the journal Scientific Reports. On average, there was a 17% improvement in participants’ color contrast vision when exposed to three minutes of 670 nanometers deep red light in the morning.
In studying the effects of deep red light in humans, researchers built on their previous findings in mice, bumblebees, and fruit flies, which all found significant improvements in the function of the retina’s photoreceptors when their eyes were exposed to 670 nm light.
“Mitochondria have specific sensitivities to long wavelength light influencing their performance: longer wavelengths spanning 650 to 900nm improve mitochondrial performance to increase energy production,” said Professor Glen Jeffery, the lead author from UCL Institute of Ophthalmology.
All the participants were aged between 34 and 70, had no ocular disease, completed a questionnaire regarding eye health prior to testing, and had normal color vision (cone function). This was assessed using a Chroma Test — identifying colored letters that had very low contrast and appeared increasingly blurred, a process called color contrast.
Using a provided LED device all 20 participants (13 female and 7 male) were exposed to three minutes of 670nm deep red light in the morning between 8 am and 9 am. Their color vision was then tested again three hours post-exposure and 10 of the participants were also tested one week post-exposure.
On average there was a ‘significant’ 17% improvement in color vision, which lasted a week in tested participants; in some older participants there was a 20% improvement, also lasting a week. However, conducting the same test in the afternoon did not seem to produce the effect.
“Using a simple LED device once a week, recharges the energy system that has declined in the retina cells, rather like re-charging a battery, said Professor Jeffery. “This simple intervention applied at the population level would significantly impact on quality of life as people age and would likely result in reduced social costs that arise from problems associated with reduced vision.”
The researchers noted that while positive effects are clear for individuals following 670 nm exposure, the magnitude of improvements can vary markedly between those of similar ages. Therefore, some caution is needed in interpreting the data. It is possible that there are other variables between individuals that influence the degree of improvement that the researchers have not identified so far and would require a larger sample size.
Full news release: www.ucl.ac.uk/news/2021/nov/morning-exposure-deep-red-light-improves-declining-eyesight
Source: University College London