Exposure to Red Light Improves Color Vision of Study Subjects

July 22, 2020

A small study shows that "photobiomodulation" with red light results in improved color vision in people that are 40 and older. The light may improve the function of mitochondria.

The mitochondria are like the power-producing batteries of the cells. But with age, they run down and the slacking off of their energy production contributes to the aging process in all tissue.

But researchers in London say they have found a simple, inexpensive way to recharge mitochondria of the cells of the photoreceptors in the retina, which are particular dense with mitochondria and prone to their power loss.

Glen Jeffery and his colleagues at the University College London reported results in the Journals of Gerontology: Series A that shining a red light into the dominant eye every morning for three minutes for two weeks improved color contrast vision by 20% ,on average, among people age 40 and older.

Jeffery said in an interview with Managed Healthcare Executive® that using red light to stimulate mitochondria is also under investigation as a way to treat diabetes and Parkinson’s disease.

“I had lots of colleagues treating me with a certain degree of derision five years ago,” said Jeffery. “They are not treating me with derision now, thankfully.”

This line of research is predicated on evidence that mitochondria absorb longer wavelength light in the red end of the spectrum and doing so activate them and improves their function. Jeffery’s results suggest that the red light has more of an effect on cones that sense color than rods, which sense low-level light.

The device that the University College London researchers used in their study costs about $15. Jeffery made a point of mentioning the low cost: “My strong message to the type of readers you have is don’t pay $20,000 for something you can pay $15 for,” Jeffery said.

But earlier this year, things were not looking so rosy for Jeffery and red light “photobiomodulation.” Jeffery and his colleagues reported results in the Journal of Clinical Medicine that showed that the red light exposure had no effect on people with macular degeneration. Jeffery said he was “bitterly disappointed” by that outcome but also learned to simplify his study design and the outcomes he was considering at as a result.

In this latest study, which included 24 people, the outcome that the researchers zeroed in on was people’s ability to see contrasts in color. The brief exposure to red light in the morning resulted in improvements in the tritan-visual axis, which people see as blue. The improvement, which was about 20% on average, was limited to people who were about 40 and older.

Jeffery said it is not surprising that there was no effect among younger people because the mitochondria in their cells haven’t aged and are performing at a high level. “It is like changing the battery in a new car — there just isn’t any point.”

Jeffery said his future research will include efforts to tease out why the red light had an effect in some people but not others. He also plans on studying macular degeneration patients: “I am going to try to bring those people back in and have another crack at them.”