How Red Light Therapy May Improve Declining Eyesight

As you get older, you may notice that it becomes harder to distinguish between different colors. You may start having trouble reading a menu in a dimly-lit restaurant. While vision changes are normal, they may soon be treatable.

Researchers from the University College London are exploring red light therapy as a treatment for declining eyesight. According to their study, published in the June edition of The Journals of Gerontology: Series A, Biological Sciences and Medical Sciences, regular exposure to red light may help improve eyesight through the actions of mitochondria and adenosine triphosphate (or ATP). 

The normal aging process is associated with a natural decline of mitochondria’s ability to produce ATP. And because the photoreceptor cells in your retina have a high energy demand—and a lot of mitochondria—the retina ages faster than any of your other organs, according to Glen Jeffery, lead study author and professor of neuroscience at University College London’s Institute of Ophthalmology.

Jeffery adds that over your lifetime, you’ll lose 70% of the ATP in your retina, which translates to a significant decline in eye function. Your photoreceptor cells no longer get the energy they need to properly perform their job.

Red Light May Help Improve Vision

Animal studies have previously shown that long wavelength deep red light can improve the function of the receptors in the retina, thus improving vision. But Jeffery and his colleagues set out to test this theory in humans for the first time.

In the small study, researchers tested eye function and the sensitivity of the rods and cones in the eyes of 24 participants (12 men and 12 women) between the ages of 28 and 72 without any pre-existing eye diseases. Once data was collected, the participants were sent home with a small LED light that emitted a deep red 670 nanometer (nm) light beam. Participants were instructed to look directly into this light beam for three minutes a day over a period of two weeks.

When participants returned to the research center to have their eyes retested, there was no measurable difference in the eye function of those under the age of 40, but those age 40 and older experienced notable improvements in the ability to detect different colors (cone color contrast sensitivity) and the ability to see in dim light (rod sensitivity).

The most significant difference was in cone color contrast sensitivity, with some people experiencing improvements of up to 20%.

Jeffery explains that the red light therapy works by “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.”

In other words, your retina absorbs the red light, and the mitochondria are effectively able to use that to produce the ATP you need to keep your eyes healthy and functioning properly.

Jeffery says that because the take-home LED devices cost just around $15 to make, he anticipates the technology will be highly accessible to the public.

Keeping Your Eyes Healthy

While red light therapy may show some promise, it's still a fairly new concept and there's not a lot of available information on the potential side effects.

"The study in question was performed on a very small number of subjects, so there is a lot of room for more research on this," Jenna Zigler, OD, an optometrist and co-owner of Eye Love, tells Verywell. "From what we know right now, potential risks are minimal, but more research is needed to know for sure."

Zigler says her number one tip for keeping eyes healthy as you age is to wear 100% UV blocking sunglasses while outdoors.

She also emphasizes the importance of nutrition.

"Filling your diet with green leafy vegetables and colorful vegetables in general may be helpful for keeping the retina healthy as you age," Zigler says. "Avoiding excess sugar and processed foods is more important than people realize."

Regular eye exams are also important. Because most eye diseases are initially asymptomatic, Zigler recommends getting a yearly comprehensive dilated eye exam so you and your doctor can catch any potential problems before they turn into a more serious issue.

"Even if you're doing red light therapy at home, it doesn't mean you won't have an eye disease that could have been caught earlier through a yearly exam," Zigler says.