There is an epic fight unfolding between the light side and the dark side of, no, not the Force, but the light spectrum itself. You will have seen the countless gadgets claiming to heal you with red light\u2014the creepy masks full of LEDs, the therapeutic light boxes, even the full-body infrared saunas. Red light, we are told, has health benefits.<\/p>\n
I will be using the term \u201cred light\u201d for ease of reading, but technically the claim is being made about a portion of the light spectrum, both visible and invisible to us, that includes red light, near-infrared, and infrared light. A more accurate term would be \u201clong-wavelength light,\u201d but for simplicity\u2019s sake, I will use \u201cred light.\u201d<\/p>\n
Red light is not very energetic. Sure, infrared light from the Sun is what we perceive as heat, and infrared lamps are used in restaurants to keep your order warm before it is served, but light can be\u00a0much more\u00a0energetic. As we pass through orange, yellow, green, cyan, and blue, light carries more energy. And that\u2019s where we encounter red light\u2019s nemesis, so-called blue light. It includes blue and violet in the visible spectrum (and possibly ultraviolet rays, which we do not see). Technically, we should refer to it as \u201cshort-wavelength light.\u201d<\/p>\n
LED lights are everywhere now. Although they often look white, they emit a lot of blue light and not much, if any, red light. Recently, I learned that some scientists were referring to this indoor lighting revolution as a public health crisis on par with asbestos. Blue light is said to be causing harm to the little energy factories of our cells, while red light is being alleged to cure, well, just about anything.<\/p>\n
This good-versus-evil battle between two different kinds of light has been blown way out of proportion, and the anecdotes and scientific studies being weaponized here deserve a lot of scrutiny.<\/p>\n
Blue light bad?<\/p>\n
A\u00a0recent study<\/a>\u00a0on indoor lighting caught my attention because of how it had been distorted by one media outlet, NewsNation. You may not be familiar with it. I wasn\u2019t. It\u2019s an American cable news network and it belongs to Nexstar Media Group, the largest television broadcasting company in the U.S. On\u00a0NewsNation\u2019s website<\/a>, this new study\u2019s results are framed as a \u201ccrisis\u201d for our cells, specifically our mitochondria.<\/p>\n What\u2019s funny is that the study itself did not look at our mitochondria. Mitochondria\u2014in its plural form, and \u201cmitochondrion\u201d in the singular\u2014are little bodies inside of our cells, and one of their jobs is to convert what we eat into energy that our cells can use. If a cell is a city, the mitochondrion is its power plant, and most cells contain hundreds of these mitochondria.<\/p>\n What the study actually did is give 11 people who worked in a gloomy building in London lit only with LED lights a desk lamp. The LED lights emitted a lot of blue light; the desk lamp was incandescent, much closer to actual sunlight and thus full of red light as well. A separate group of 11 people was not given a desk lamp. Both groups underwent a vision test that specifically looked at colour discrimination. For example, a red letter \u201cT\u201d was presented on top of a blue background, and the letter was very faint. Their eyes had to be sharp enough to distinguish the \u201cT\u201d amid the background. This test was done at the beginning of the experiment and after two weeks of the first group using their desk lamp.<\/p>\n The group with the lamp did better at discerning these letters, and not just right after the experiment but months later, one of the authors\u00a0claimed<\/a>.<\/p>\n Again, nothing about mitochondria; but this experiment is part of a larger research programme by Dr. Glen Jeffery trying to prove that red light is good and blue light, at least in isolation, is bad, and that the reason for this involves our mitochondria.<\/p>\n Dr. Jeffery is a professor of neuroscience and researcher at University College London and is\u00a0the\u00a0scientist at the eye of this red-light-versus-blue-light storm. His theory is that different types of light have different effects on our mitochondria, and that it all boils down to water. Jeffery\u00a0refers<\/a>\u00a0to the parts of mitochondria that produce energy as \u201cthese little wheels, these pumps that spin around, but they spin around in water.\u201d And because the pump is so small, the amount of water is tiny. He was told that at that scale, water is viscous (as proposed\u00a0here<\/a>). He believes that when red light is shone on the body, it makes this mitochondrial water\u00a0less viscous. The wheel, like a motor, can thus spin faster. Cells make more energy. Blue light in the absence of red light keeps that water viscous like molasses, and the wheel spins much more slowly.<\/p>\n The wheel he is referring to is called\u00a0ATP synthase<\/a>, which does indeed have a rotor that spins. When we invented the wheel, we were unknowingly reproducing something inside of us we couldn\u2019t even see.<\/p>\n But to believe Jeffery\u2019s grand theory of light\u2019s benefits and harms on our health through our mitochondria, we need the green light from scientific evidence, and unfortunately, I am not quite seeing it.<\/p>\n Red light good?\u00a0<\/p>\n If we suspect blue light of making people sick, then experimenting on people with it is akin to asking research participants to take up smoking to see what will happen. It\u2019s unethical. So the majority of the research has examined if red light, instead, benefits the human body and if its rays can rescue ill health allegedly caused by blue light exposure.<\/p>\n At first light, the papers I read are either very preliminary and thus not informative, or their results beggar belief. They are often done in mice or rats or fruit flies, and the control groups, when they exist, are not as rigorous as they should be, in my opinion. Animal research is often a required stepping stone in doing experiments in humans, but we are not giant mice.<\/p>\n What is alleged in these papers is that red light helps with vision loss due to ageing; that it makes fruit flies live longer and improves their memory and mobility; that it protects bees from stress; and that it prevents blood sugar spikes after a meal. This already sounds a little too good.<\/p>\n But it is Jeffery\u2019s appearance on\u00a0Huberman Lab<\/a>, the popular \u201cscience\u201d podcast hosted by Andrew Huberman, Ph.D., that raised my eyebrow. Huberman\u2019s second career, outside of the halls of Stanford University, has blessed him with accolades, but his show often spreads fear-inducing misinformation (on topics like\u00a0sunscreen<\/a>, for example) while promoting\u00a0highly questionable products<\/a>. The episode in which Jeffery was interviewed about red light was interrupted by\u00a0five\u00a0separate sponsor ad reads: a financial investment service, the pseudoscientific\u00a0green smoothie powder<\/a>\u00a0for which Huberman is a well-paid ambassador, a water filter the value of which hinges on a study conducted by the\u00a0pseudoscientific Environmental Working Group<\/a>, a paid service to have hundreds of unnecessary medical tests conducted, and of course a provider of red light therapy products whose light boxes\u00a0cost between US$ 549 and 11,099<\/a>.<\/p>\n My eyebrow started going up after Jeffery described his invasive experiment in humans in which participants were starved overnight, given a big cup of glucose to drink, had their finger pricked repeatedly to test blood glucose levels while they had a tube up their nose to detect oxygen consumption. \u201cIt\u2019s hard getting subjects for this one. [\u2026] I even dragged my son in as a subject for that one,\u201d he\u00a0says<\/a>, sounding like he\u2019s making light of it. As a grad student, I was taught I could not participate in my lab director\u2019s experiments because I couldn\u2019t give informed consent. I wanted to make my boss happy so I could graduate, and that desire could be exploited in a research context. Asking his son to get multiple invasive blood tests and have a tube shoved up his nose for a study rings an ethical alarm bell in my mind.<\/p>\n My eyebrow was raised some more when he described how little amount of red light was needed to achieve a benefit. Sure, you can shine a red-light flashlight a few inches from your eyes for a few minutes, but by mistake they used a flashlight in the lab that was low on batteries and that ended up delivering\u00a01 milliwatt per centimetre squared<\/a>\u2014a very, very dim red light\u2014and improvements in vision were measured there too.<\/p>\n My eyebrow kept moving up my forehead when I heard mentions of \u201crogues\u201d and \u201cmovers and shakers,\u201d of the need for contrarians in science. Jeffery proudly talks of a dermatologist friend who claims that people who get\u00a0lots\u00a0of sunlight actually live longer even though unprotected sun exposure leads to sunburn which is a risk factor for skin cancer. This dermatologist, he says, no longer has any dermatologist friends anymore because of his belief. I\u2019ve heard this Galileo gambit before, where scientific research is portrayed as crusted over until a revolutionary comes along with a crazy theory he wants proven right. This idea that the so-called tenth dentist is always right because contrarianism is good is just misguided.<\/p>\n My eyebrow went full Vulcan when he mentioned\u00a0the failed clinical trial<\/a>\u00a0in which he tried to improve the eyesight of women with age-related macular degeneration using red light. They got no effect, but their husbands, who were recruited as the control group, did improve! This is not seen as potential noise in their experiment and a failure of the control group to be a good control group; rather, the women\u2019s disease was interpreted as being too far advanced, whereas the husbands were healthy enough to benefit from the light.<\/p>\n (Jeffery mentioned an independent replication that seems to show that red light\u00a0does\u00a0improve vision in macular degeneration. He is referring to the\u00a0LIGHTSITE II trial<\/a>, which was significantly impacted by the COVID-19 pandemic and which has received\u00a0criticism<\/a>. It was also financed and conducted by the company that makes the red light device tested. You can read the LIGHTSITE II trial\u2019s authors rebuttal\u00a0here<\/a>, but even they agree that \u201ca small study interrupted by COVID is difficult to draw strong conclusions from.\u201d A\u00a0Cochrane review<\/a>\u00a0of the evidence before LIGHTSITE II stated that we do not know if this type of therapy works for macular degeneration.)<\/p>\n My eyebrow finally reached my hairline\u00a0at the very end of the podcast<\/a>, when red light was insinuated as the saviour for people with certain genetic diseases. Mitochondria have their own DNA molecule, and the genes this molecule contains code for proteins the mitochondria need to do their job. Mitochondrial disease arises when one of these genes is mutated and the protein it codes for doesn\u2019t work well. Jeffery told the story of children who have a type of mitochondrial disease so severe that their ability to make energy is impaired and they usually die by the age of 25. Parents reached out to him, and he told them they might want to consider red light therapy. Lo and behold, Jeffery reports a \u201cgut-wrenching improvement.\u201d Within a month or so, one of these children was semi-mobile again. He sobbed when he saw a video of her walking to school.<\/p>\n He said too few people in the London area suffer from this condition, so he was unable to recruit enough to do a proper randomized clinical trial. All we have are anecdotes.<\/p>\n The way in which Jeffery summarizes the benefits of red light therapy on Huberman\u2019s show is incredible, in the literal sense of the word.<\/p>\n Apparently, you can shine red light in your eyes and not for long. Its effect lasts for days. And it doesn\u2019t even have to be bright. It can be very dim. And it doesn\u2019t even have to be your eyes; any patch of skin will do, like a little rectangle on your back. And you don\u2019t even need to shine it directly there; red light from the Sun scatters off of plant leaves and you get it this way too.<\/p>\n But somehow, sunlight isn\u2019t enough. Somehow, working indoors in an environment lit by LEDs is a major health crisis and the red light we\u2019re already getting isn\u2019t enough. On the podcast, Jeffery\u00a0said<\/a>, \u201cThere\u2019s a group of us that are shuffling around corridors, all mumbling to one another, saying, \u2018How big a stink is this?\u2019 [\u2026] Some of [the members of this group] are saying, \u2018This is an issue on the same level as asbestos.\u2019\u201d<\/p>\n It just doesn\u2019t add up.<\/p>\n Jeffery makes it sound like we all live and die in LED boxes, never seeing any other form of light. But we don\u2019t. We spend time in parking lots walking to and from our cars. We drive with the windows down. We walk to the pharmacy. We mow the lawn and work on our garden. We walk our dog. If red light is so potent that very little of it is needed for a very short amount of time, we\u2019re already getting it. There\u2019d be no need to panic people about the harms of LEDs if they could be reversed by a homeopathic dose of red light, which is way less than what almost all of us get on a daily basis.\u00a0<\/p>\n You can\u2019t have it both ways. You can\u2019t say that LED lights are so damaging that they are an important cause of every illness\u2026 and also claim that red light is a cure-all in tiny doses for a few minutes at a time, even reversing diseases baked into our genes!<\/p>\n If Jeffery\u2019s theory is correct, then red light therapy is redundant because brief exposure to sunlight is enough. And what does he say\u00a0when Huberman asks him<\/a>\u00a0if we can indeed get the same effect with sunlight? \u201cI\u2019m not going to spend whatever is left of my career hunting that down.\u201d I was stunned.<\/p>\n This casts his motivation in a bad light, in my opinion.<\/p>\n When all you have is a hammer<\/p>\n I\u2019m not dismissing the whole story. LED lights can be overly clinical and depressing. Ask any interior designer and they will remind you of the importance of lamps with warm light bulbs, especially in the evening, to create a cozy, relaxing atmosphere. Incorporating warm bulbs both at home and in work environments is not a bad idea. Moreover, staying indoors under artificial lights is not good for us: it makes us sluggish and can impact our circadian rhythm, and it\u2019s usually associated with sitting down for too long and staring at screens. Going outside\u2014with adequate protection from sunburns\u2014is beneficial, and few people would argue against that.<\/p>\n But to ascribe so much illness\u2014low sperm count, blood glucose spikes, age-related vision loss, obesity\u2014to blue light and, contrapuntally, to insist that a tiny bit of barely visible red light can reverse all of this is a hard pill to swallow. The use of red light to treat disease is part of the field of photobiomodulation, and\u00a0as I\u2019ve argued previously<\/a>, its early research findings are coated in a thick,\u00a0thick\u00a0layer of hype.<\/p>\n Dr. Jeffery ends his podcast conversation by stating that \u201ceverything is pointing towards light bulbs,\u201d and his\u00a0id\u00e9e fixe\u00a0gets amplified and twisted in the media, with\u00a0name-calling of LED lights<\/a>\u00a0as \u201cflickering synthetic weapons\u201d conducting \u201cwhole-body attacks\u201d and proposals of completely evidence-free\u00a0protocols to \u201cdetox\u201d from blue light<\/a>. This adds an unnecessary anxiety to our already anxious lives.<\/p>\n When your entire research career is aimed at proving one thing, it\u2019s a hammer-and-nail situation. What I would recommend is going outside, basking in the sunlight for a bit, and looking at other causes of disease. Putting a spotlight on something is not bad, unless it blinds you to what is happening outside of that tiny splash of light.<\/p>\n Take-home message:
– Some researchers and influencers are claiming that LED lights, by emitting a lot of blue light and not enough red light, are causing a slew of health problems.
– They will also claim that red light (meaning red, near-infrared, and infrared light) shone on a small part of the body in tiny amounts has significant health benefits and can counteract the dangers of blue light.
– These claims are greatly exaggerated and require much better scientific evidence to prove.
– One researcher has said that a bit of red light therapy appeared to reverse the debilitating symptoms of a genetic disease that typically kills people by the age of 25, which is an extraordinary claim that requires extraordinary evidence.<\/p>\n