Over the years, I have become convinced sunlight is one of the most essential nutrients for the body. Unfortunately, since no one has a financial interest in promoting sunlight (and it hence has no lobbyists), almost everything we hear instead focuses on why it’s terrible for us. For example, dermatology transformed itself from one of the least desirable specialties in medicine into one of the highest paying ones by rebranding its members as cancer fighters, which required scaring everyone senseless about the sun (while omitting that a lack of sunlight is what causes fatal skin cancers). Despite the billions now spent each year on skin cancer, the total death rate from it remains almost entirely unchanged (all of which is discussed here).A similar story has played out with the light inside our homes. In 2022, the federal government effectively banned the incandescent bulb on the grounds most of its output is “wasted” as infrared, even though a rapidly growing body of research shows our bodies depend upon that infrared. For this reason, I feel it is prudent to explore why this seemingly simple switch could be so impactful on our lives.Note: after I originally explored this subject, many readers here shared that they greatly dislike how fluorescent and LED lighting feels to be around.The Importance of SunlightPrior to dermatology’s war on the sun (which is immensely misguided as dangerous skin cancers are due to a lack of sunlight exposure), the value of sunlight was widely recognized in medicine. For example, in the early 1900s, heliotherapy (sunbathing) was used with great success for treating many otherwise incurable conditions such as the 1918 influenza1 and tuberculosis.1 The existing data in turn shows sunlight provides an immense degree of benefit:• A large study found high solar UVB exposure halved one’s risk of breast and prostate cancer.1• A 20-year study of 29,518 women found that avoiding the sun made one 60% more likely to die, with the greatest benefit of regular sun exposure being a reduced risk of dying from heart disease.1 Likewise, in a 2024 analysis of the UK Biobank, both measures of UV exposure that were examined were associated with a lower risk of dying from any cause, from cardiovascular disease and from cancer,1 and when 88,905 participants wore light sensors for a week, those with brighter days and those with darker nights were each less likely to die over the following 8 years.1• Sunlight is critical for mental health, and many workers suffer immensely without it (e.g., in hospital night shift workers, a lack of sunlight exposure was linked to worse mental health1).Note: I really got this point once, where after a long period of hospital night shifts under fluorescent lights, I noticed I was becoming clinically depressed (which has never otherwise happened to me). I went home and bathed under a full spectrum bulb, at which point I almost instantly felt better.Typically, sunlight’s benefits are attributed to vitamin D. However, I have long suspected that many of the benefits of vitamin D are not due to the vitamin itself but rather that its elevation indicates the body is having regular sunlight exposure. For example, when 24 healthy volunteers were exposed to UVA (which does not produce vitamin D) at a dose equivalent to about 30 minutes of summer sun, their arteries dilated and their blood pressure dropped, as nitric oxide stored in the skin was released into the circulation.1 Similarly, a meta-analysis found that spending an hour or more a day in the summer sun was associated with a 16% lower risk of breast cancer, whereas simply living somewhere with more ambient UV was not.1The Incandescent Bulb BanNatural light contains a wide range of frequencies, whereas artificial light tends to have a much narrower range which differs greatly from what biology evolved to handle. This is easiest to see by comparing bulbs. A standard white LED emits a sharp spike of blue at around 450nm, a broader hump of yellow, and almost nothing past 700nm. An incandescent bulb, like the sun, emits a smooth curve that keeps rising through the red and continues past 2000nm, so most of what it produces is infrared we cannot see.1In 2007, Congress passed a law which, if the Department of Energy did not finish its own lighting standards in time, required it to prohibit the sale of any general purpose bulb producing less than 45 lumens per watt. In 2022, the Biden administration put that prohibition into effect, and in 2024 finalized a second rule which raises the minimum to roughly 120 lumens per watt in 2028.1 As incandescent bulbs produce 10-18 lumens per watt,1 this was a ban, and the 2028 standard will eliminate almost everything besides LEDs.The problem is what a lumen is. It does not measure light, but rather how bright light appears, using a curve adopted in 1924 that weighs each wavelength by how strongly it registers in our daytime vision. Green and yellow hence count the most, blue and deep red count for very little, and ultraviolet and infrared count for almost nothing. Decades after it was adopted, a separate set of light-sensing cells was discovered in the retina which set the body’s clock rather than form images, and respond most strongly to blue light around 480nm (which the lumen curve counts at roughly one-seventh the value of green). So under this standard, a bulb that puts most of its energy into infrared is wasting it, while the blue spike in an LED registers as a minor part of its output despite being the part the body’s clock reacts to the most.In 2023, 248 scientists who had collectively published 2,697 papers on light and the circadian clock reached a consensus that the blue-enriched LEDs replacing our older bulbs disrupt circadian rhythms, that this disruption raises the risk of breast cancer, obesity, diabetes and sleep disorders, and that LED bulbs with a high blue content should carry a label warning they “may be harmful if used at night.”1Note: blue light is used by the tech industry to make screens significantly more addictive (e.g., recently a tech investor and a UC Berkeley neuroscientist shared that switching phones to greyscale made them much less addictive1,2).Similarly, when 52 household bulbs were recently measured, cool white LEDs and compact fluorescents were each estimated to suppress melatonin by about 12%, warm white LEDs by 3.6%, and incandescent bulbs by 1.5%,1 while a study of actual homes found those lit with energy efficient bulbs had nearly double the circadian-active light in the evening of those still using incandescents, and that nearly half of all homes were bright enough to suppress melatonin by 50%.1 This, in turn, plays a major role in the modern insomnia epidemic as avoiding that light at night is a key foundation of many sleep restoration regimens (which is particularly tragic as the sleeping pills we use have a wide range of serious issues—but to protect their market the FDA waged a ten year crusade to outlaw one of the most effective and restorative sleep aids ever discovered).Note: in 2016, the American Medical Association warned against the blue-rich LED street lights most cities were installing, as they are at least five times more powerful at suppressing melatonin than the (orange) sodium lamps they replaced, create a glare that worsens nighttime vision for drivers, can damage the retina, and disorient nocturnal wildlife.1The lost light is also highly consequential. Glen Jeffery’s team at University College London has spent years showing that deep red and infrared light (670-900nm) increases mitochondrial energy production, whereas the 420-450nm blue which dominates LEDs suppresses it. In 2024, they showed that shining 670nm red light on people’s backs for 15 minutes reduced the blood sugar spike from a glucose drink by around 27%.1 Then, in 2026, in a London office building lit entirely by LEDs (and with windows coated to reflect infrared), they placed ordinary 60 watt incandescent desk lamps around the benches of 11 workers for two weeks, while 11 others served as controls. The color contrast vision of every worker near the lamps improved (by roughly 25%), nothing changed in the controls, and the improvement lasted for two months after the lamps were taken away. The authors noted that incandescent bulbs are being phased out on the basis of a standard which only considers visible light, and that their attempts to recreate the missing spectrum with infrared LEDs had limited success.1The LIT ActIn 2025, Senator Mike Lee of Utah, who chairs the Senate Energy and Natural Resources Committee, introduced the LIT Act (S. 1568) to undo this.1 It removes general purpose light bulbs from the Department of Energy’s efficiency program, cancels the 2022 and 2024 rules, and prevents the agency from writing new ones, while leaving LEDs on the shelf for anyone who wants them.In September 2026, the bill finally received a hearing, where the Department of Energy testified in support of it, the ranking Democrat defended the ban on the grounds it “is supported by industry” (and submitted a letter from the lighting industry’s two trade groups, who do not want to compete with incandescent bulbs), and Senator Lee said the ban harms consumers “not just for economic reasons, not just for aesthetic reasons, but for a whole host of reasons.”What I found most striking was that in over 17 minutes of debate on cost, bulb lifespan and the power grid, the health effects of these bulbs were only alluded to, in Lee’s closing remark.Two weeks later, on September 30, the committee voted 11 to 9 along party lines to send the bill to the full Senate.1 The manufacturers’ trade group immediately announced its members (who’ve invested billions in LEDs) no longer make incandescent bulbs and have no plans to resume, and warned that repeal would let “Chinese products flood the market,”1 which is as clear a statement as you will get of why the industry wanted the ban kept. The bill still needs 60 votes on the Senate floor and passage in the House, and with the Senate in recess for the elections, no floor vote is expected this year.1 So this is the point where it will either die quietly or move, and given how close the committee vote was, that will likely come down to whether Senators hear from the people who want it.John OttMuch of what we are now learning was first observed decades ago by John Ott, a pioneer of time-lapse photography (e.g., Disney hired him) who realized the plants he filmed were reacting to the light he filmed them with, and then discovered similar effects in animals and humans.1 Much of his work was predicated on recognizing that UV for the most part does not pass through glass. Some of his most interesting findings were:•Plants: amplifying the UV in sunlight (by placing aluminum under squash plants) increased their yield five-fold and eliminated both viral and insect infestations, while tomato plants dying from a contagious virus recovered and bore fruit once they received unfiltered sunlight.•Fertility: in a 5-year study with over 2000 chinchilla breeders, standard incandescent bulbs yielded litters that were 60-75% male, whereas “daylight” incandescent bulbs reversed this to 60-75% female. Similarly, placing a cathode ray color TV near his breeding program caused rats to go from 8-12 young per litter to 1-2.•Animal health: 97% of mice born under natural UV light survived to maturity versus 61% under pink fluorescent lights, and cancer-prone mice under pink light died in 7.5 months on average, while as the light was improved, their lifespan progressively lengthened (up to 16.1 months). Additionally, male mice kept under dark blue fluorescent light became obese, much as in 2025, mice exposed to the 420-450nm blue light which dominates LED bulbs were found to gain weight rapidly,1 while in 2019, fruit flies raised under white LEDs lived half as long as those kept in darkness (a loss which almost entirely disappeared once a yellow filter removed the blue).1• Cavities: hamsters fed a cavity provoking diet averaged 2.2 cavities under fluorescent light with UV added, versus 10.9 under cool white fluorescents.1• Behavior: male rats (which are normally removed before a litter is born so they will not eat it) instead cared for their young under natural light, minks became vicious under pink light but docile enough to handle with bare hands under blue, and a radio station developed severe personnel problems two months after pink fluorescents were installed to “brighten the mood,” all of which resolved within a week of the bulbs being replaced.• Schools: in a 1973 Chicago pilot study, first graders under standard cool white fluorescents demonstrated nervous fatigue, irritability, fidgeting and frequent lapses of attention, whereas within a week of full spectrum lighting being installed, they settled down and paid attention (e.g., one boy who had been in constant motion taught himself to read), and were later found by their dentists to have one-third the number of cavities. Similar results were then obtained in California.1 Ott also traced a school with five times the national rate of leukemia to two classrooms where the curtains had been kept closed under warm fluorescent lights, and once new teachers reopened them, the cases disappeared.• Glasses: after developing severe hip arthritis that nothing (including sunbathing) helped, Ott’s glasses broke, and he noticed an immediate and progressive improvement that was later confirmed by x-ray, leading him to suspect a primary route of light into the body was the eyes (as he had worn sunglasses while sunbathing). Others who followed his regimen of getting natural light to the eyes (without glasses or windows in the way) saw hay fever, Graves’ eye disease, diabetic eye damage and recurrent skin cancers improve, and when a doctor had 15 cancer patients follow it for a summer, 14 did not progress (the one who did had still worn regular glasses).While Ott’s belief that glasses deprive the eyes of wavelengths they need never gained traction in medicine, ophthalmology recently arrived at a version of it. Japanese researchers found that violet light (360-400nm, right at the edge of UV) suppresses the progression of nearsightedness, and that children who wore eyeglasses (which block it) had their eyes elongate faster than children wearing contact lenses which let it through.1 They traced this to a violet-sensitive photoreceptor in the retina,1 and when they measured violet light around Tokyo, found it was abundant outdoors and essentially absent indoors, as windows, eyeglasses and modern lighting all filter it out.1Read the Whole ArticleThe post What Modern Light Bulbs Are Doing to Us appeared first on LewRockwell.