STUDIES: Avoidance of sun exposure is a risk factor for all-cause mortality: results from the Melanoma in Southern Sweden cohort (Journal of Internal Medicine) The health benefits of the great outdoors: A systematic review and meta-analysis of greenspace exposure and health outcomes (Environmental Research) Treatment with 670 nm light up regulates cytochrome C oxidase expression and reduces inflammation in an age-related macular degeneration model (PLOS ONE) Light stimulation of mitochondria reduces blood glucose levels (Journal of Biophotonics) Longer wavelengths in sunlight pass through the human body and have a systemic impact which improves vision (Scientific Reports) A Pilot Study Evaluating the Effects of 670 nm Photobiomodulation in Healthy Ageing and Age-Related Macular Degeneration (Journal of Clinical Medicine) Light exposure during sleep impairs cardiometabolic function (Proceedings of the National Academy of Sciences)

Modern Indoor Lighting Has Created a Public Health Crisis - Here’s Why Incandescent Bulbs Can Help 👇 Your indoor lighting environment has a tremendous impact on your health. Each wavelength (or color) of light plays a specific role in regulating your biology. Most people have no idea how dramatically modern lighting—and I mean just since the early 2000s—has altered the biological signals their bodies evolved to depend on. ➡️ Our Historical Light Environment (until very recently) Over the course of billions of years, life on Earth evolved under the full electromagnetic spectrum of natural sunlight — from invisible long-wavelength infrared, through the visible spectrum, to invisible short-wavelength ultraviolet. For most of human history, we effectively brought the outdoor light spectrum indoors. Fire, candlelight, and incandescent light bulbs are all thermal sources of light. When measured with a spectrometer, they emit a wide, balanced spectrum that is relatively low in short-wavelength light (such as blue) and smoothly increases into longer wavelengths (such as red), with abundant invisible infrared—which we experience as heat. This balance matters. Shorter-wavelength light carries more energy and is inherently stimulatory. In isolation, that stimulation can become stressful and damaging. In nature, however, short-wavelength light is always balanced by abundant long-wavelength light that is restorative. For reference, natural sunlight contains roughly (depending on location and time of year): ~8% ultraviolet (shorter wavelength) ~42% visible light (ROYGBIV) ~50% infrared (longer wavelength) If we were exposed only to long-wavelength light (red and infrared), we’d lack the stimulation needed to initiate steroid hormone production and mobilize energy for the day. If we were exposed only to short-wavelength light, energy production would suffer and aging would accelerate — our mitochondria would struggle to function. ➡️ The Evolutionary Shock of LED Lighting Everything changed abruptly in the early 2000s, when light-emitting diodes (LEDs) rapidly replaced incandescent bulbs. Unlike fire or the Sun, LEDs are not thermal light sources. They emit very narrow bands of visible light while removing infrared entirely. This was framed as an efficiency win — LEDs produce visible light without “wasting” energy as heat. But that so-called waste heat is biologically meaningful. Infrared light plays a critical role in: - Building exclusion-zone water inside and around our cells - Supporting mitochondrial energy production - Penetrating tissues to support repair processes Removing long-wavelength light while isolating high-energy short-wavelength light creates a signal that does not exist in nature — and one we are not adapted to. Chronic exposure to blue-enriched light without balancing red and infrared has been linked to: - Sleep and circadian disruption - Diabetes and metabolic dysfunction - Attention, focus, and cognitive issues - Myopia and macular degeneration - Systemic energy loss tied to mitochondrial stress ➡️ Infrared Light is an Essential Nutrient for Our Mitochondria Long-wavelength light penetrates deeply through tissues in a way short-wavelength light does not. Inside the body, infrared light interacts directly with mitochondria to support energy production. One mechanism involves water inside and around mitochondria. Long-wavelength light alters the viscosity of this water, allowing ATP synthase—the molecular turbine at the end of the electron transport chain—to spin more efficiently and generate more ATP. Additionally, cytochrome c oxidase (Complex IV of the electron transport chain inside the mitochondria) absorbs light in the near-infrared range, supporting metabolic water production. This metabolic water becomes charge-separated exclusion-zone water, which is critical for cellular energy production, cell membrane integrity, detoxification, and more. Infrared light also stimulates localized melatonin production inside mitochondria, where melatonin acts as a potent antioxidant—neutralizing excess reactive oxygen species that are a normal (and healthy) byproduct of oxidative phosphorylation. In short: long-wavelength light is an essential nutrient for mitochondrial function. And mitochondrial function determines the overall state of health. Modern indoor lighting has removed this nutrient almost entirely—while simultaneously increasing exposure to isolated short-wavelength light that promotes inflammatory and hypoxic conditions inside the body. ➡️ It’s Not Just LEDs — It’s Indoor Living Even without artificial lighting, modern windows are designed to block heat transfer — which means they filter out much of the red, infrared, and UV light while allowing proportionally more blue light to pass through. The result is an indoor environment that is blue-shifted by default. Combined with screens and LED lighting, we’ve created living spaces that bear little resemblance to the conditions under which human biology evolved. These alien light environments are affecting us, our children, our pets, our mental health, our physical health, and our future. ➡️ So What Can You Do? There is a widespread lack of physics education when it comes to light and its biological effects, and economic incentives often (usually) override public health considerations. As consumers, we need to drive the market and make our voices heard. Incandescent bulbs, while largely phased out, are still available for “decorative” use and remain the most biologically reliable indoor lighting option. As awareness grows, “circadian-friendly” or “full-spectrum” LEDs are entering the market. These can be useful tools, but it’s important to understand their limitations. LEDs still emit narrow wavelength spikes and generally lack infrared. They do not replicate the smooth, full spectrum emitted by natural thermal light sources. We’ve studied isolated wavelengths—but we know far less about how the full spectrum works together as an integrated biological signal. This is why the simplest, most affordable, and most reliable option remains the incandescent bulb (and a fireplace, if you have one). ➡️ Balancing Your Indoor Light Spectrum Incandescent bulbs can help you replicate a natural spectrum of outdoor light that your biology expects. Think of this as spectrum balancing. Indoors — between screens, LED light fixtures, and window-filtered daylight — you are exposed to a very blue-enriched environment lacking red and infrared. Your goal is to add those missing wavelengths back in. - During the day, incandescent bulbs can help counter overly blue indoor environments. Placing one near your workspace can provide supportive ambient long-wavelength light. - At night, red incandescent bulbs are preferable to red-only LEDs (because they contain infrared) for protecting circadian rhythms and preventing melatonin suppression. - Non-toxic beeswax candles and fireplaces are also excellent low-blue, long-wavelength light sources. - Circadian-friendly LEDs can be useful when incandescents aren’t an option — just remember they are still a compromise, not a replacement for thermal light. ➡️ A Seasonal Reminder As we move deeper into winter and the holiday season, people spend more time indoors under artificial lighting. That lighting can either be stress-inducing — subtly affecting mood, sleep, and behavior — or it can support calm, connection, and restoration. This season, consider your light environment and how it’s shaping the experience of everyone exposed to it. Use what we now understand. Reclaim your space. Support your biology. And bring a bit more of nature’s balance back into your home. ☀️