Imagine stepping into the world and finding colors fading, becoming less vibrant, just as autumn leaves do before falling. This was the reality for many participants of a scientific study testing the use of red light therapy on eyesight that was published in the Journals of Gerontology.
After only two weeks of gentle red light therapy, their eyes saw crisper colors and even needed less light to see.
Not too long after the study came out, a red light therapy enthusiast self-treated his eyes with a random red light therapy device. Due to the intensity of the light, he permanently damaged his retinas.
So is red light good for the eyes? While it’s true that the Journals of Gerontology study showed that red light therapy is good for certain aspects of vision, that does not mean that all red light is safe for the eyes.
Red and infrared wavelengths are completely safe in low to moderate intensities and do have the capacity to improve vision when correctly applied. However, A bright light of any color can cause permanent damage to the retina, and that means permanent partial blindness.
Industry thought leaders with truly good intentions argue that infrared and red light cannot hurt the eyes. It’s true that “red and infrared” light doesn’t hurt the eyes. That’s because it’s not the “red” or the “infrared” that causes the damage. The wavelength is not the problem. The intensity is the problem.
I’ve already given you a major hint as to whether you need goggles for red light therapy, and here’s the rest of that story in my article One Test to See if You Need Red Light Therapy Goggles
Is Red Light Good for the Eyes? The Eye Study in Perspective
The Journal of Gerontology study showed that 670 nm (which is the wavelength, by the way; 670 nanometers distance from the peak of one wave to the peak of another is one of the many shades of red light) red light through closed eyes improved the ability to see the color blue.
It did not cure short- or far-sightedness. It did not improve macular degeneration (although other studies have, which we’ll get into below).
These results were nice, but not nearly as impressive as the public relations reach would imply.
I just wish people would look at what they’re doing before getting excited about the vision study.
Red light therapy is a tool, like a hammer. Just as you can hammer a nail to fix a chair, you can also hammer your thumb to the point of breaking it.
The study does not give you a universal license to shine any light into your eyes. The brightness can cause blindness. For the love of God and all that is holy, speak to an ophthalmologist before using any light therapy on the eyes.
The Eye Health Light Therapy Study That Started it All
A diverse band of 24 individuals enlisted in this study, ranging in age from 28 to 72. They started each day basking in red light therapy for a modest 3 minutes. This continued for two weeks.
At the outset, those who were at least 40 years old had an average of 20% loss in color contrast. It was as if someone had cranked down the saturation knob on their world. This was the color sensitivity portion of the study.
All the participants, regardless of age, had light sensitivity issues. They needed more light to see than people with healthy eyes. This was the light sensitivity portion of the study.
After two weeks of bathing in red light therapy, the vibrancy of colors returned to the older participants. They regained an average of 22% improvement in color sensitivity. The younger subjects had less to no color vision loss, and so did not have significant improvements. Their color sensitivity was still healthy.
Remarkably, three out of four participants in the light sensitivity group, including even some who hadn’t seen their 40th year yet, also noted a significant improvement. These subjects now needed less light to see clearly.
The Red Light Therapy Vision Improvement Study Summary
- The retina, with the highest concentration of mitochondria in the body, experiences a significant decline in the function of its light-sensing cells, rods, and cones, from the age of 40.
- Red light therapy, particularly at the wavelength of 670nm, has been identified as a potential solution to mitigate this decline and restore vision.
- A clinical study from The Journals of Gerontology demonstrated the effects of red light therapy on 24 healthy volunteers aged between 28 and 72.
- After two weeks of daily 3-minute therapy, older individuals experienced a 22% improvement in color vision, and 75% of participants in the light sensitivity group showed improvement.
- The aging process affects rods and cones differently; by age 70, about 30% of rods tend to die off, whereas cones decline in function but do not die.
- Cones processing blue light are more susceptible to decline due to fewer mitochondria compared to cones that process green or red wavelengths.
- Red light therapy improves low-light vision by enhancing the function of rod cells and helps to restore and protect color vision by boosting the function of cone cells.
- The therapy is most effective in the morning when mitochondria are most efficient at producing energy and can better absorb light to boost energy production.
Why Red Light Therapy Improved Color and Light Sensitivity
The eyes use “rod” cells to pick up light, and “cone” cells to interpret that light as colors. Rods see light and cones see colors.
Those cells are jam-packed with mitochondria, the organelles that create the biological batteries that power cellular functions.
The cells that see blue light, however, have fewer mitochondria than those that see red and green.
Rods begin to decline after age 30 and lose 30% of their function by age 70. This loss is linked to problems with mitochondria, the energy factories of our cells. The eyes need more light to see as we age.
The cone cells that are responsible for seeing the color blue start life with a weakness that gets worth with age. Blue cones have fewer mitochondria than green and red cells, so they have less energy to do their blue-seeing work. The ability to see blue declines with age because the eye’s blue cones run out of battery makers.
That’s where red light therapy comes in. Red light therapy’s superpower is powering the factory that makes the batteries that power the eyes.
Benefits of Red Light for the Eyes
Red light therapy does more than increase the ability to see blue, and to see with less light.
Red light therapy has been shown to help combat age-related macular degeneration (AMD), which is the leading cause of vision loss in adults over the age of 50.
Red light therapy has also been found to be effective in treating other eye conditions such as diabetic retinopathy and glaucoma.
The same mechanism that helps eyes see blue improves AMD, retinopathy, and glaucoma symptoms.
The increase in energy production (biological batteries) is accompanied by red light therapy’s other superpowers: inflammation reduction, and the reduction of oxidative stress.
Can Blue-Light Blocking Glasses Help Eye Health?
Blue light blockers protect the eyes from harmful blue light that comes from computer and phone screens.
This blue light disrupts the production of melatonin and causes insomnia.
Blue blockers do help protect the eyes from blue light but do not protect the eyes from overly intense light of any color.
Red light is both good and bad for the eyes, depending on how it is delivered. Only the shortest wavelengths of light are inherently dangerous due to nothing more than their wavelengths. You would not subject your eyes to daily X-rays for this reason. That light is so energetic that it knocks electrons off your DNA.
X-rays and gamma-ray wavelengths are inherently dangerous.
The wavelengths of red, infrared, blue, green, and yellow are safe for the eyes unless they are delivered with bright intensity. Then they’re not safe.
For the benefits of light therapy for the eyes, speak to your ophthalmologist about using red light therapy for glaucoma, AMD, color and light sensitivity, and retinopathy therapies.
Shinhmar H, Grewal M, Sivaprasad S, Hogg C, Chong V, Neveu M, Jeffery G. Optically Improved Mitochondrial Function Redeems Aged Human Visual Decline. J Gerontol A Biol Sci Med Sci. 2020 Sep 16;75(9):e49-e52. doi: 10.1093/gerona/glaa155. PMID: 32596723.Benlahbib M, Cohen SY, Torrell N, Colantuono D, Crincoli E, Amoroso F, Semoun O, Jung C, Souied EH. Photobiomodulation therapy for large soft drusen and drusenoid pigment epithelial detachment in age-related macular degeneration: a single-center prospective pilot study. Retina. 2023 Apr 6. doi: 10.1097/IAE.0000000000003805. Epub ahead of print. PMID: 37027819.
Burton B, Parodi MB, Jürgens I, Zanlonghi X, Hornan D, Roider J, Lorenz K, Munk MR, Croissant CL, Tedford SE, Walker M, Ruckert R, Tedford CE. LIGHTSITE II Randomized Multicenter Trial: Evaluation of Multiwavelength Photobiomodulation in Non-exudative Age-Related Macular Degeneration. Ophthalmol Ther. 2023 Apr;12(2):953-968. doi: 10.1007/s40123-022-00640-6. Epub 2023 Jan 2. PMID: 36588113; PMCID: PMC9805913.
Di Paolo M. Sequential PBM-Saffron Treatment in an Animal Model of Retinal Degeneration. Medicina (Kaunas). 2021 Oct 3;57(10):1059. doi: 10.3390/medicina57101059. PMID: 34684096; PMCID: PMC8538989.
Siqueira RC, Belíssimo LM, Pinho TS, Dourado LFN, Alves AP, de Paiva MRB, Ajero U, Cunha ADS. Short-Term Results of Photobiomodulation Using Light-Emitting Diode Light of 670 nm in Eyes with Age-Related Macular Degeneration. Photobiomodul Photomed Laser Surg. 2021 Sep;39(9):581-586. doi: 10.1089/photob.2021.0005. PMID: 34546108.
Muste JC, Russell MW, Singh RP. Photobiomodulation Therapy for Age-Related Macular Degeneration and Diabetic Retinopathy: A Review. Clin Ophthalmol. 2021 Sep 2;15:3709-3720. doi: 10.2147/OPTH.S272327. PMID: 34511875; PMCID: PMC8421781.
Henein C, Steel DH. Photobiomodulation for non-exudative age-related macular degeneration. Cochrane Database Syst Rev. 2021 May 6;5(5):CD013029. doi: 10.1002/14651858.CD013029.pub2. PMID: 34097768; PMCID: PMC8273038.
Muste JC, Kalur A, Iyer A, Valentim CCS, Singh RP. Photobiomodulation therapy in age-related macular degeneration. Curr Opin Ophthalmol. 2021 May 1;32(3):225-232. doi: 10.1097/ICU.0000000000000742. PMID: 33606405.
Grewal MK, Sivapathasuntharam C, Chandra S, Gurudas S, Chong V, Bird A, Jeffery G, Sivaprasad S. A Pilot Study Evaluating the Effects of 670 nm Photobiomodulation in Healthy Ageing and Age-Related Macular Degeneration. J Clin Med. 2020 Apr 2;9(4):1001. doi: 10.3390/jcm9041001. PMID: 32252424; PMCID: PMC7231137.
Merry GF, Munk MR, Dotson RS, Walker MG, Devenyi RG. Photobiomodulation reduces drusen volume and improves visual acuity and contrast sensitivity in dry age-related macular degeneration. Acta Ophthalmol. 2017 Jun;95(4):e270-e277. doi: 10.1111/aos.13354. Epub 2016 Dec 18. PMID: 27989012; PMCID: PMC5484346.
Fuma S, Murase H, Kuse Y, Tsuruma K, Shimazawa M, Hara H. Photobiomodulation with 670 nm light increased phagocytosis in human retinal pigment epithelial cells. Mol Vis. 2015 Aug 21;21:883-92. PMID: 26321863; PMCID: PMC4544713.