Staring at a deep red light for just three minutes can drastically improve deteriorating vision, according to a new study published in the journal Scientific Reports. Impressively, the improvements from a single light session persist throughout the week, but this improvement only works when applied in the morning.
The researchers explain that eyesight tends to decline with age as the mitochondria in our photoreceptor cells begin to deteriorate, becoming less efficient at producing energy in the form of a molecule called adenosine triphosphate (ATP). However, previous research shows that mitochondrial performance can be enhanced with long-wave light that has a deep red color, and exposure to these wavelengths can restore function in these cells.
The retina contains two different types of photoreceptor cells: rods and cones. Rods help us see in low light, but can die over time if their energy demands are not met. Cones allow us to see in color. More importantly, if they don’t get enough ATP, the cones don’t die, they just have a reduced function. This means that increasing mitochondrial efficiency is likely to restore vision.
The same researchers published a study last year that revealed that exposure to dark red light for three minutes a day over a two-week period improved the color vision of people over 40 by 22 percent. In their most recent study, they sought to determine whether a single exposure could produce similar benefits.
They recruited 20 participants, ages 34 to 70, who each spent three minutes staring at a dark red light with a wavelength of 670 nanometers. Because previous research has shown that mitochondrial function fluctuates throughout the day, the authors insisted that participants do their light treatment between 8 and 9 a.m.
The researchers tested each participant’s eyesight after three hours and found that a single exposure to dark red light increased color vision by an average of 17 percent. In some older participants, the degree of improvement was over 20 percent.
The study authors conducted follow-up tests on half of their volunteers seven days later and found that these benefits lasted for a full week. However, when the experiment was repeated using dark red light exposure in the afternoon, no improvement in color vision was observed.
Commenting on these findings, study author Glen Jeffery says, “A single exposure to long-wave dark red light in the morning can significantly improve vision reduction, a major health and well-being problem that affects millions of people worldwide.” Three minutes of deep red light exposure once a week can be done while making coffee or listening to a podcast, and such a simple method can transform eye care and vision worldwide.”