Interviews and Presentations on Light Physiology

• Professor Glen Jeffery (University College London) discussed the implications of infrared light on human health, focusing particularly on its relationship with mitochondria — the cellular powerhouses responsible for energy production

• there is growing awareness of the health impacts of light exposure, particularly as modern environments have shifted dramatically from natural sunlight to artificial light sources, often deficient in critical wavelengths

• infrared light has demonstrated the ability to enhance ATP production in mitochondria, potentially countering age-related declines in energy levels and cognitive function

• blue light has the opposite effect, and excessive blue light exposure can impair mitochondrial function, leading to negative health outcomes such as obesity and cognitive decline

• we need balance between short and long wavelengths

• exposure to long wavelengths can also improve vision and reduce blood sugar

• Prof. Jeffery calls for a revival of infrared and broad-spectrum lighting solutions in our environment

• ophthalmologist Dr. Montgomery discusses the profound implications of light exposure for optimal health, stemming from his personal journey through a debilitating neurological condition

• faced with the prospect of brain surgery, he turned to research on quantum and circadian biology, ultimately unveiling how natural sunlight and its components play a foundational role in well-being

• key themes: critical relationship between light exposure and mitochondrial health, the impact of artificial blue light, and the significance of the circadian rhythm

• the eye is not merely an optical organ but also acts as a "sky clock," which intricately regulates the body's biological rhythms

• understanding the healing potential of natural sunlight may offer an accessible and fundamental approach to improving public health

• light profoundly impacts our eyes, skin, and overall physiology

• these physiological effects are nonlinear: you don't necessarily need large doses, but you need exposure to the full spectrum, with the right timing of its various components

• she describes many details of known circadian, mitochondrial, cardiovascular, hormonal, and other light physiology interactions

• most people spend approximately 85-90% of their time indoors, combined with lots of screen-time and processed food, missing out on being in tune with nature as the foundation of health

Our comment: we at Pixun fully embrace the message of increasing outdoor daylight exposure and reducing screen-time! As much as indoor display use is a must, we offer the healthiest option by bringing daylight directly into the digital screen.

• we’re experiencing “the largest reduction in solar exposure in the history of humanity”

• since there is a stark contrast between natural sunlight and artificial indoor lighting, this has significant health implications

• whether in sunshine or in shade, near-infrared (NIR) light is abundant outdoors but missing in indoor spaces

• energy regulations have forced indoor electric light options towards blue-light-dominant LED lighting, which neglect critical NIR wavelengths that our bodies require for proper physiological functioning

• “the body goes to extreme lengths to localize near-infrared light” — to where it’s needed the most, e.g. to the fovea: the majority of photons reaching the retina do not go through the pupil but are collected through the eyelid and sclera and channeled to the back of the eye

• we are far from really understanding how these things work; there have been many studies on red/NIR light therapy, but conducting studies with sunlight is very challenging

Interviewer:

• therefore, studies focus on picking a specific wavelength; when positive effects are observed, this wavelength is added to a lamp to boost health outcomes

• then, when a new wavelength shows positive effects, we want to add that too… “It starts to become absurd, really, to think that it’s just those two wavelengths. It’s really the sunlight! That is what matters. Getting back to, should we eat reassembled chemicals in highly processed foods that taste good and include all the things that we know are healthy, or should we just eat real food? Cos it turns out that that’s better for you. So probably, what the best thing to do is to get the whole spectrum. Even though there have been no studies on every single wavelength . . . It’s the full spectrum that we need; it’s not this wavelength or that wavelength in my lamp.”

Zimmerman:

• “The problem is that the lighting industry, particularly the Department of Energy (DOE), has implemented rules that complicate matters. They have gone down the LED route and do not want to inform customers that they left something out . . . All the circadian light sources out there are trying to use wavelengths between 400 and 700 nanometers and adjust the color to mimic sunlight, but without the near-infrared component, you are essentially wasting your time with all the different color-shifting technologies the industry is employing. That’s the problem we’re trying to address: we can easily incorporate near-infrared light; the technology is available and not hard to implement.”

• “I once spoke with an engineer from a major window glass company who explained that they were blocking near-infrared light from entering buildings, which was changing biological responses. He noted that as they shifted transmission further into near-infrared for hospitals, they observed better patient care results but never understood why. Unfortunately, they eventually hit a limit imposed by government regulations that required them to block more near-infrared light. This has led us to create an artificial environment that is likely one of the worst possible for human health.”

• red light enhances mitochondrial activity, resulting in increased use of sugar for ATP production

• Professor Jeffery noted, "If we work mitochondria hard, they draw more sugar from your blood," underscoring the transformative potential of light therapy in metabolic health

• for this reason, red light exposure reduces blood glucose spikes after sugar intake (as demonstrated already in human studies)

• the mentioned study showed a reduction in blood glucose levels by approximately 17%, a finding he deemed "not marginal"

• ongoing research indicates similar effects in individuals with type two diabetes, suggesting broad applicability

• blue light does the opposite: it slows down mitochondria, resulting in an increased blood glucose spike after sugar ingestion (only shown in animals so far), potentially implicated in weight gain

• this reinforces concerns about our modern environment dominated by artificial lighting, particularly as exposure to blue-rich LED lighting at night becomes more prevalent

• In essence, substantial benefits lie in returning to natural light exposure, a fundamental element often overlooked in discussions surrounding modern lifestyle choices.

• millions of years of evolution have finely tuned our biology to utilize the broad spectrum of sunlight, which includes essential near-infrared (NIR) wavelengths

• an indoor lifestyle with modern lighting solutions, such as LEDs, provide no NIR, thereby depriving us of the benefits that this spectrum offers

• NASA astronauts, coming back from the space station, suffer from mitochondrial dysfunction. Some of this can likely be attributed to their unnatural light environment and lack of NIR exposure.

• traditional incandescent bulbs provided a broad spectrum of light, including NIR, but have largely been replaced by energy-efficient options that only produce visible light

• They compare the current state of artificial light deprivation to the historical case of sailors suffering from scurvy due to a lack of vitamin C from fresh produce. Just as it took time to identify and correct that deficiency, the general public is now beginning to recognize the negative impacts of inadequate light exposure — a realization that requires re-education and awareness.

• “This isn't rocket science.” We have the power to reconnect people with their natural environments, promoting outdoor living and harnessing light for well-being. However, the challenge lies in overcoming institutional resistance and ingrained societal norms surrounding light exposure.

• on the podcast of the American Academy of Optometry, Dr. Andrew Pucker interviewed Dr. Kim Duong about a paper evaluating the use of repeated low-level red light therapy for controlling myopia in children

• the prevalence of myopia is growing, affecting half of the global population by 2050

• this also increases the risk of ocular pathologies such as retinal detachments and cataracts

• red light of 635 to 650 nm wavelength can be used as an alternative treatment, effectively reducing axial length and refractive error, suggesting its potential to slow myopia progression

• presently approved in China and still under investigation in the United States, the therapy offers a practical, low-cost solution

• “The interaction between light and myopia is complicated.”

• Our comment: these interactions are complicated and not yet well understood, but some aspects of how light spectrum plays a role in emmetropization have an extensive literature. Please also see some of this literature under our “References” tab.

• Dr. Fosbury, who has transitioned from a successful career in astrophysics to exploring biological challenges, emphasizes the crucial role sunlight plays in nourishing life on Earth, arguing that modern lighting solutions have deprived humans of essential infrared wavelengths necessary for optimal mitochondrial function

• there is an evolutionary dependence of life on sunlight, particularly infrared photons, which penetrate skin and tissues deeply, allowing cellular processes to function efficiently

• a return to thermal light sources, such as incandescent bulbs, as well as more outdoor activity would be beneficial for health

• "He said 'There's a problem with the office environment that we don't understand.' And of course both of us said to ourselves, well we do understand what this problem is, why don't you listen to what we say? This problem is that people are living under pure visible illumination in the built environment. And this is a complete rake with the evolutionary history of life on the planet. This is the first time that life forms on the planet have been consistently irradiated by just visible light. And frankly, it doesn't work. Life doesn't work like that."

• “It's gonna be very complicated to figure out all the interactions of infrared light with biological systems. There are probably many many of them. Hundreds, maybe thousands of interactions of light with biological systems. We're beginning to see the first smattering of those.”

• “I think the general concept of withdrawing the full spectrum of sunlight from our surroundings in the built environment (fortunately, not in the natural, but in the built environment), this is the problem we're facing. And you know, in my opinion, the gradual decay in public health that we're seeing now, and it's quite rapid and it's growing in seriousness, the fundamental problem behind this is the fact that we're starving people of the full spectrum of sunlight”

• Professor Glen Jeffery discusses his extensive research on aging and its implications for eye health, particularly focusing on the role of mitochondria

• mitochondria, often referred to as the body’s “batteries,” are crucial for energy production within cells

• the retina contains the highest concentration of mitochondria and therefore is heavily impacted by mitochondrial decline

• he explored using red light to recharge these mitochondrial batteries, which possibly slows the aging process and mitigates diseases such as age-related macular degeneration

• while the first clinical trial failed, hopeful outcomes have also emerged, indicating that red light therapy may reduce the rate of cell death in the retina

• the human visual system evolved to process images from nature, with no flicker and low spatial periodicity, following natural image statistics

• unnatural lighting conditions, particularly flicker from electric lights and certain computer screens, can elicit negative reactions, such as headaches and anxiety

• apparent spatial patterns created by flicker during rapid eye movements can interfere with the patterns of fonts when we read, decreasing reading efficiency and increasing fatigue or inducing headaches

• these effects can play a disruptive role at high frequencies as well (up to 10 kHz)

• higher frequency is not always better: in certain conditions, sensitivity is greater at 300 Hz than at 100 Hz

• while many people may not consciously perceive flicker of higher frequencies, it nonetheless affects visual perception and comfort: “The take-home message is that flicker can be detrimental even if you can’t see it.”