I’m very easy to distract with good light. A room can be a perfectly ordinary room, and then the sun moves a few inches and suddenly I’m looking at the wall like it has done something extraordinary. Which, in a very quiet way, it has.
So the idea that some wavelengths can travel through parts of our bodies immediately gets my attention. We tend to think of skin as a firm boundary: the outside stops here, the inside begins there. Light is considerably less interested in that tidy arrangement.
But the original version of this article took an interesting research story and made promises it couldn’t support. It treated sunlight, experimental red light, near-infrared exposure, and medical eye treatments as though they were different versions of the same thing. They aren’t.
The research is worth understanding without that shortcut. Scientists have measured certain wavelengths after they passed through body tissue. Small studies have reported changes in specific vision tests following carefully controlled light exposure. There is also a prescription light-based treatment authorized in the United States for a defined group of people with dry age-related macular degeneration.
Those findings don’t establish that sunlight repairs everyone’s eyesight, that a glowing hand proves healing, or that a red panel from the internet is suitable for your eyes. Don’t look at the sun or shine a household therapy device into your eyes to reproduce something you read here.
I still think this is a wonderful subject. I just want the wonder to belong to the actual science. Light can be beautiful, biologically important, useful in medicine, and capable of causing damage. We don’t have to choose only one of those descriptions.
The light we see is only part of the story
Visible light occupies a narrow part of the electromagnetic spectrum. Red sits toward the longer-wavelength end of the light our eyes detect. Near-infrared lies beyond that familiar visible range. You can have infrared radiation present without seeing a red glow.
A wavelength tells us something about the radiation. It doesn’t tell us everything about the source, the energy delivered, or what a particular exposure will do. “Red” is a broad description when the question concerns a biological experiment.
The earlier article called longer waves “slower.” That was misleading. In vacuum, electromagnetic waves travel at the same speed. A longer wavelength corresponds to a lower frequency and lower energy per photon, rather than a photon taking a leisurely stroll while blue light rushes past it.
I like the leisurely-photon image, admittedly. It has strong Sunday-morning energy. But it belongs in the metaphor drawer, and we should close that drawer before explaining an experiment.
This distinction also helps with product claims. Two devices can both look red while producing different spectra and different exposures. Our eyes are useful for enjoying a sunset. They aren’t a substitute for the instruments needed to characterize a treatment device.
Can light really pass through us?
Some light is reflected at a tissue’s surface. Some is scattered, changing direction. Some is absorbed. Depending on wavelength and the tissue involved, a fraction can travel far enough to be detected elsewhere.
That doesn’t mean the body becomes transparent in the everyday sense. A detector picking up a weak signal after transmission is very different from being able to look through someone as though they were a window.
It also matters what kind of camera produced an image. An infrared-sensitive camera can reveal information an ordinary photograph cannot. Its display converts that information into something we can see. The image isn’t necessarily showing what your eyes would have seen in the room.
This is why I’d be careful with a photograph of a hand that appears to glow. It may be a striking demonstration of transmission under particular conditions. It doesn’t, by itself, demonstrate that cells were repaired, inflammation changed, or vision improved.
Those are separate questions requiring separate measurements. A photograph can make us curious enough to investigate. It can’t do the entire investigation for us, no matter how convincing the glow looks.
The 2025 paper behind the story
In July 2025, Glen Jeffery and colleagues published a study in Scientific Reports examining light transmission and visual performance. They measured sunlight after it passed through the chest, then conducted laboratory exposures using near-infrared light centered around 850 nanometers.
The vision component used small groups: 13 participants received back exposure, five had their heads shielded to exclude ocular exposure, and seven received a sham exposure. Researchers tested colour-contrast thresholds before and 24 hours afterward. In the shielded group, the blue-yellow measure improved significantly; the red-green change did not reach statistical significance.
That is an intriguing result, especially because it raises a question about effects beyond the illuminated area. It is also a small, short-term experiment. It didn’t show that ordinary sunlight reverses an eye disease or that a morning walk replaces an eye examination.
The sunlight-transmission measurements and the controlled vision experiment were different parts of the paper. Combining them into “the sun healed their vision” removes a distinction essential to understanding what was tested.
The authors discussed possible mechanisms, including mitochondrial and systemic signaling effects. The experiment didn’t establish the complete biological pathway. That unanswered question is part of the finding, not an inconvenience we should edit out.
AI-generated daylight illustration above. This is not an infrared research image or evidence of tissue repair.
The earlier red-light experiment asked another question
A 2021 UCL study examined brief exposure to 670-nanometer deep-red light and colour-contrast performance. Twenty participants received a single morning exposure with a study device; ten were tested again a week later. A smaller afternoon comparison found no corresponding improvement.
UCL reported an average improvement of about 17% in the colour-contrast measure after morning exposure. Participants had no ocular disease. This wasn’t a trial showing that people with cataracts, glaucoma, or macular degeneration could repair those conditions with a red torch.
The researchers also reported considerable variation between individuals. A result in a small group is a reason to investigate, not a promise about what will happen to any particular person.
The 670-nanometer eye-exposure study and the 850-nanometer body-exposure study aren’t interchangeable protocols. Different wavelengths, exposure locations, study designs, and questions matter. Quoting the duration from one while recommending the device from another creates a new experiment that neither paper tested.
I know the brief-exposure detail is tempting. “A few minutes” sounds like the kind of health habit I might actually manage. But a convenient duration doesn’t travel independently of the equipment and conditions that made it meaningful.
Colour contrast isn’t the same as throwing away your glasses
Vision is a collection of abilities. Reading small letters, distinguishing colours, seeing in dim light, noticing something at the edge of your visual field, and focusing an image are related without being identical.
The National Eye Institute explains that light is focused onto the retina, where photoreceptors convert it into electrical signals that travel through the optic nerve to the brain. The cornea, lens, retina, and the rest of that system all contribute to the result.
A change in one test doesn’t tell us that every part of the system has improved. A colour-contrast threshold concerns how faint a difference a person can detect under specified conditions. It isn’t automatically a change in their glasses prescription or a restoration of damaged tissue.
Think about tasting wine. Becoming better at distinguishing two similar aromas doesn’t necessarily mean you can now identify every bottle blind. One measured ability can change without turning into an improvement in every other ability we casually bundle together.
That comparison has limits, obviously. But it helps me remember to ask a simple question when I see “vision improved”: which part of vision, measured how, and for how long? Those words are where the actual finding lives.
Why mitochondria keep appearing in this research
Mitochondria are structures inside cells that help convert energy from food into forms the cell can use, including ATP. They participate in a much larger biological system, rather than acting as isolated little batteries waiting for a charger.
They attract attention in light research because metabolism and cellular performance may respond to certain exposures. The retina is an especially interesting place to study energy demands because maintaining visual function requires continual cellular work.
But “mitochondria are involved” isn’t a complete explanation. It doesn’t tell us which molecule absorbed the light, how signaling changed, whether the effect was direct or indirect, or what that means for an individual patient.
The earlier article presented cytochrome c oxidase as though it supplied a settled answer to every red and near-infrared result. The 2025 authors themselves discussed a more complex and uncertain picture. A plausible mechanism is something researchers can test; it isn’t a stamp that approves every product using the same vocabulary.
I still find mitochondria fascinating. Tiny biological structures helping sustain everything from a thought to a muscle contraction are already impressive. They don’t need to be described as drinking sunlight or remembering an ancient language to keep my attention.
What photobiomodulation means
Photobiomodulation is the term commonly used for biological effects sought through particular light exposures, often involving red or near-infrared wavelengths. It describes an area of research and treatment approaches. It doesn’t identify one universal therapy with one universal result.
When someone says “light therapy works,” I want the rest of the sentence. Works for which condition? With which equipment? In which patients? Compared with what? Over what period? At what risk?
A treatment can have evidence for one purpose while remaining experimental for another. Evidence involving skin doesn’t automatically establish an eye treatment. Evidence in animals can help shape a question without settling what happens in people.
This is where wellness language becomes slippery. A word like “cellular” can sound reassuringly precise while allowing the claim around it to remain extremely vague. Everything happening in a body involves cells somewhere. That doesn’t tell us whether the proposed treatment produces a worthwhile clinical benefit.
I’m comfortable being hopeful about a field while asking these questions. In fact, I think hope benefits from them. If a treatment is useful, clear measurements and careful comparisons help us identify that usefulness rather than bury it under a pile of attractive promises.
There is a real prescription treatment—but the details matter
The FDA authorized marketing of the Valeda Light Delivery System in 2024 for certain patients with dry age-related macular degeneration. It is a prescription device used by eye-care professionals, with specific eligibility criteria. Its authorization doesn’t apply to every form of declining vision.
The FDA review describes a combination of amber, red, and near-infrared wavelengths and a defined treatment schedule. After about two years, the average visual-acuity advantage over the comparison group was approximately one line on the study chart. The review also includes limitations, contraindications, and uncertainties about benefit after treatment stops.
That is meaningful progress. It is also much more specific than “red light restores eyesight.” A clinical device, a selected patient group, and a measured outcome give the result its practical meaning.
If you have dry AMD, an ophthalmologist can explain whether this treatment is relevant to your situation and how it fits with your existing care. A consumer panel sharing one of its wavelengths isn’t automatically an equivalent treatment.
I’d rather report a modest, well-defined benefit accurately than promise a transformation to everyone. People making decisions about their sight deserve the actual size and limits of the evidence.
A newer study looked at everyday lighting
In January 2026, Edward Barrett and Glen Jeffery published a study involving 22 adults working in LED-lit environments with little daylight. Eleven received supplemental incandescent lighting for two weeks; eleven formed a comparison group. The researchers reported improvements in colour-contrast testing after the lighting change.
This is an interesting extension of the research because it examined a working environment rather than a brief targeted exposure. It also remained a small study. Participants’ movements and all of their light exposures weren’t tightly controlled, and the groups worked in different spaces.
The findings don’t demonstrate that every LED harms the retina or that changing your lightbulbs treats an eye disease. The title makes a broad argument; the experiment provides a narrower set of observations that need further testing.
That distinction can be easy to lose because lighting feels so familiar. We all have a room we think is too harsh, too dim, or strangely unpleasant. It’s tempting to connect a paper immediately to that experience. The connection may be worth investigating without being established already.
This is a research direction to follow, rather than a reason to panic about every overhead light or rush out and replace everything in the house.
Daylight and the body clock are another part of the picture
Light also helps regulate circadian timing. The National Institute of General Medical Sciences describes daily rhythms affecting sleep, hormone levels, temperature, and other functions. Light and darkness provide important information to the body’s timing system.
That doesn’t make circadian biology identical to photobiomodulation. Feeling more alert after daylight exposure is not proof that an aging retina has been repaired. Two responses can involve light without sharing the same mechanism, dose, or clinical meaning.
This is one of those places where the word “natural” does too much work. Daylight is natural. So are darkness, seasonal changes, cloudy afternoons, and the very inconvenient timing of a winter sunset. Our relationship with light is complicated enough without reducing it to good red photons and bad blue photons.
For me, the useful distinction is between a daily routine and a treatment claim. Enjoying time outdoors can be part of an ordinary day. Prescribing exposure to address a medical condition requires another level of evidence and guidance.
I can appreciate a brighter morning without claiming I know what happened to every mitochondrion involved. Honestly, I would struggle to keep track of that many tiny participants before coffee.
Sun protection still belongs in the story
Sunlight includes ultraviolet radiation, and UV can harm the eyes and skin. NIH guidance recommends sunglasses blocking at least 99% of UVA and UVB, often labeled UV400, along with a wide-brimmed hat. Cloud cover doesn’t guarantee that UV exposure is low.
Don’t look directly at the sun, including at sunrise or sunset. The presence of wavelengths being studied for beneficial effects doesn’t cancel the hazards of the source as a whole. Closing your eyes is not a substitute for using a device according to appropriate safety instructions.
The original article said I no longer thought of the sun as something to shield against. That was the wrong implication. Curiosity about light and sensible protection belong together. Sunscreen, protective clothing, shade, and proper eyewear don’t interfere with our ability to admire the day.
I think we sometimes treat a precaution as though it makes an experience less beautiful. Sunglasses don’t stop the ocean from being blue. A hat doesn’t make a garden less lovely. Protecting the body you’re using to enjoy the view seems like a perfectly reasonable part of enjoying it.
The research doesn’t require anyone to earn a benefit by tolerating glare, heat, discomfort, or a longer exposure than they need.
Why a red panel isn’t a home eye prescription
A clinical protocol includes much more than wavelength. The light output, exposure geometry, distance, duration, treatment area, schedule, and device safeguards all affect what is being tested. The intended use matters as much as the colour of the glow.
A device marketed for skin or general wellness may not be designed for direct ocular exposure. A mask, a wand, a panel, and an ophthalmic instrument can place light near the face in very different ways. They shouldn’t be treated as interchangeable simply because a product page mentions mitochondria.
The safest interpretation of the research is not “find something approximately red and copy the number of minutes.” It is that controlled exposures deserve controlled evaluation. If a study interests you, bring the paper and the exact device information to an eye-care professional before considering treatment.
I’m preserving the original article’s shopping links below, but I’m correcting what they imply. They aren’t a list of proven vision-restoration tools. The old recommendation to use a wand around the eyes with the eyes closed wasn’t justified by the studies discussed here.
It’s possible to be curious about a product without converting curiosity into a medical endorsement. That distinction should be clear before anyone spends money.
What would make the evidence stronger?
I’d like to see larger, well-controlled studies with clearly described devices, representative participants, and follow-up long enough to tell us whether an effect lasts. Independent replication would help establish which findings are reliable across settings and research groups.
I’d also want outcomes that tell us what changes in everyday life. A sensitive laboratory test can detect something real without showing that a person reads more comfortably, navigates more safely, or needs a different prescription.
That doesn’t make laboratory outcomes unimportant. They can reveal effects worth pursuing. It simply means the next question remains the next question, rather than becoming an answer because we’re excited.
The same applies to safety. A small trial with no major problem observed cannot establish safety for every age, eye condition, medication, or device. A carefully selected research group doesn’t represent everyone who might encounter a compelling headline.
I know this sounds like a lot of questions for something as ordinary as light. But ordinary things become medical interventions when we apply them with the intention of treating a condition. At that point, asking for evidence is a way of taking the possibility seriously.
Vision changes deserve attention
If your eyesight is changing, an eye examination is more useful than trying to diagnose the problem through a general article about cellular energy. Different causes require different responses. Don’t delay established care while experimenting with a light device.
The National Eye Institute identifies a sudden increase in floaters, flashes, or a curtain-like shadow across vision as possible signs of retinal detachment requiring immediate attention. Sudden vision loss or severe eye pain also warrants urgent assessment. Those aren’t situations to monitor through a home light experiment.
I’m including this because hopeful research can accidentally become permission to wait. “Maybe this will help” can sound gentle while still delaying something important. The purpose of learning about an emerging treatment should be to ask better questions, not to avoid finding out what is actually wrong.
It’s fine to arrive at an appointment curious. Bring the study, ask about its relevance, and let the discussion include the limitations. A good question doesn’t become less interesting because the answer is “not for your particular condition.”
The part of the story I still love
I’m definately keeping the wonder. Some wavelengths can move through tissue in ways our eyes can’t directly show us. Scientists can build instruments to measure that passage, test what changes afterward, and discover that a question is stranger than it first appeared.
That is already enough to make me look at a sunlit room differently. I don’t need to imagine photons rewriting my entire body or a walk restoring everything age has changed. The real interaction between light and biology has plenty left for us to understand.
I still like the phrase “vessels of light” as poetry. As a medical explanation, it needs help from measurements, control groups, and a careful description of what happened. The poetry can invite us into the subject. It shouldn’t write the treatment instructions.
So I’ll keep admiring the light on the wall, protecting my eyes, and following the research. The room doesn’t have to promise me anything. Some mornings, the way it changes is worth noticing all by itself.
A little light in the everyday routine
For a softer start to the morning, this sunrise-style alarm lamp is an option to explore. You might also come across these blue-light-filtering glasses while thinking about your screen routine. I’d keep both in the everyday-accessory category, with questions about retinal disease going to an eye-care professional.
If light-based skincare or general wellness has caught your curiosity, there’s a red and near-infrared panel, a cosmetic facial wand, and a cosmetic light-therapy face mask to compare. Each has its own intended use, so read the manufacturer’s directions and eye-protection instructions carefully. These consumer products serve different purposes from the controlled vision studies discussed above.
Keep cosmetic and general-wellness lights away from your eyes. Any treatment involving ocular exposure belongs in a discussion with your eye-care team, using a device appropriate for that purpose.
Related Reads You Might Enjoy
Just 20 Minutes of Sunlight a Day Stimulates Over 200 Antimicrobial Peptides
The Invisible Symphony: How the Universe Flickers Through Our Lives Without Us Knowing
The Sun Isn’t Yellow: A Mind-Bending Dive into Light, Space, and the Lies Our Atmosphere Tells
The Sunscreen You Never Knew You Had: How Your Skin’s Bacteria Might Be Saving You from the Sun
The Brain That Forgot How to Wander: Why Short Videos Might Be Our Newest Addiction
The Ring of Fire Is Waking Up: Quakes, Eruptions, and the Deep Breath of the Planet
The Whispering Cure: Limewashed Trees, Natural Pesticides, and the Disappearing World of Insects
Sources and further reading
Updated October 2026. This article is general information, not individual medical advice or a home eye-treatment protocol.
