Lighting Commentary

Another Voice on Good Lighting

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I have been talking about the relationship between light and health for a decade. It was probably a lecture at a distant LightFair that set my curiosity running. I started seeking out articles, research reports and other documentation to fill in my information gap. While not a doctor, I eventually developed a continually-evolving lecture on the topic. New information arrives. Science discovers more nuance to its initial findings. Better studies are conducted. More concise data is shared and made available. Ten years (perhaps more) since I sat in a cold conference room at a LightFair convention, science is still not ready to make definitive decrees about rock-solid solutions, but as many posts have indicated, the mounting evidence supports better lighting leads to healthier people.

I thought of my message and my journey and the stones in the road as I read an amazing article in The New York Times Magazine. (July 10, 2022) “The Time of Your Life” (also entitled, “The Quest by Circadian Medicine to Make the Most of Our Body Clocks”) by Kim Tingley. Initially, I felt this was a very easy to understand description of the internal “clocks” that help our body function. If for no other reason, I suggest reading this article. The author goes a bit deeper than I do, but it still is easy to comprehend.

Farther into the article, we are introduced to a doctor who is attempting to change the medical community because of this unearthed information. The cycles in out body create peaks and low periods over the 24 hour day. For example, we typically have the highest blood pressure at 6:30PM and the lowest blood pressure right before a huge jump at 6:30AM. Our body is warmest at 7:00PM and coolest at 4:30AM. We are most alert at 10:00AM and have the best coordination at 2:30PM. These and other swings are very predictable and they impact about half of the roughly 20,000 genes we have in our body.

Early in the scientific discovery process, this doctor found that medication, when taken in sync with specific aspects of the systemic oscillation delivered optimal results. The drugs were more effective and more impactful when compared with administration at any other time of the day. By simply altering the specific time medication is brought into our bodies, we could enjoy better, perhaps optimal results!

You’d think the medical community would leap onto these findings. Better results with virtually no downside? Even if, after five years of added study, they determined that timing was not the thing that accelerated performance, there is no downside. The patient is still taking the same medicine and the results are the same results. It should have been a win-win. Yet he met with a less than receptive medical community.

I feel his pain. I talk about lighting and have talked about lighting for almost 20 years. I’m not alone. There are many lighting professionals who are trying to help people move toward better lighting. Initially, the goal was better functioning spaces and now, an effort to increase healthy results. Some larger corporations have embraced the idea, but the concept has largely been ignored, even at health care facilities. Because good lighting is “different” than the lighting currently used and because the timing of drug intake is “different” than normal medication distribution, change is a bit like Lloyd Bridges’ command to turn an aircraft carrier around to pick up his blown-off hat in the movie “Hot Shots!,” possible, but unlikely…and very difficult.

In the future, we will be using light that is more sensitive to the circadian (and other) cycles in our body and hospitals and prescription instructions will time the intake of drugs to coincide with the optimal cycle movement. In-hospital med-pass efficiency will likely take a back seat. The reason is the preponderance of evidence. Healthy lighting will probably be more complicated. Some will acquiesce and others will treat it like smoking warnings and COVID immunization shots. The majority will heed the advice, but a percentage will ignore their doctor and lighting pros. You can take a horse to water, but you can’t make him drink.

Technical Lighting Help

Non-Visual Photoreceptors

What the heck are non-visual photoreceptors and why do I care about them? I’m not a research scientist, so let me explain this in the way I understand it. Please don’t use this simplified explanation in your application for a Nobel Prize!

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When I started to research the color of light and its impact on human health, perhaps ten years ago, I became aware of the circadian cycle built into the human body (and almost every animal.) Our understanding of the circadian rhythm is actually new science. It was first realized in 2000. At the time, we began to learn about non-visual receptors in our eyes (iPRGC) whose singular job is to detect levels of blue light, thereby turning on and off the body’s production of melatonin, which in turn drives our circadian. More recently, scientists have learned that there are other factors that control this important body-clock.

An educational session at LightFair 2021 talked about new research that has uncovered additional non-visual photoreceptors that help our body function, based on the color of light with which they interface.

In a previous post, (Baseball and Lighting) I reminded readers that our body was engineered with only natural light in mind. The body needs blue light during the day and darkness at night. Unfortunately, we have chosen, over the last 100 years or so to live in opposition to the natural environment, employing artificial light. That artificial light presents to our body wavelengths different than the sun’s and different than what we need, hence the health problems we are encountering.

Melanopsin regulates the circadian with input from the iPRGC in the eye. New research indicates we have other “light sensing proteins,” opsins that have their own specific demand for light and their own specific reason for needing it. Because artificial light does not now deliver that type of wavelength, adverse medical conditions are occurring. Opsin 5, Neuropsin is located in the brain, skin, retina and cornea. Opsin 4, Encephalopsin is found in the brain, skin, retina and fat cells. That means there are tissues in our body that are light sensitive.

It is believed that a reduction of the light anticipated by these opsins is responsible for elevated retinopathy in infants, increases in myopia and the regulation of metabolism. Most every lighting system used today is designed, understandably, for the body’s visual system. In the future, we will likely need to design and employ systems that address the needed wavelengths of light by these opsins.

How Will This Be Done?

Again, we should remember the sun. The sun delivers light at every wavelength, in varying values. By looking at the research and the levels of light required, engineers can create artificial light commensurate with the needs of our visual system AND our non-visual receptors.

The direction in which light reaches us is also important. As you know, most artificial light comes to us from overhead, but the sun travels through the sky in an ever-changing pattern starting very low in the morning, overhead at midday and again, near the opposite horizon in the evening. That means our bodies anticipate more vertical light than we currently receive. We should expect this solution to come in fewer ceiling flush lights, more task plane lighting and even illuminated walls and panels.

At this point, there are some products on the market that address this need. As the research continues and grows, expect to see and hear more. Just remember, like so much in lighting lately, change is afoot!

Technical Lighting Help

Circadian Supportive Lighting

In my last blog post about the future of lighting, I only mentioned circadian-supportive lighting in passing. I received a few comments that suggested I should be more-bullish on this type of light. Here’s why I stand by my opinion.

Over the last decade, I have attended countless lectures and panel discussions covering light, more specifically how light relates to health and our perception of color. Following the completion of the first session, I was immediately optimistic for the future. Initially, change seemed so easy. Unfortunately, the more I learned, the dumber I got.

Color wasn’t just CCT and Color Rendering. After each lecture, another wrinkle was added. Chromaticity, spectral power distribution, gamut, tri-stimulus values and metamerism all turned a simple solution into a complicated problem. What seemed like a “no-brainer” quickly turned into a much more complicated issue.

I remember attending an annual Energy Star conference. An open session on color damn-near turned into a bar fight between an audience member and the moderator. The topic was not a political fight, a sports-based disagreement or even a spurned lover. This was a harsh exchange about each person’s understanding of the color of light. Certainly not the typical argument you’re likely to overhear at Danny’s Tavern. (Feel free to insert the name of the local watering hole of your youth.)

Early on, the importance of circadian-based lighting in the future seemed obvious. Its increased use became my assumption, too. The more I learned and saw of the trajectory of LED, I began to pull back on the notion. LED is getting cheaper and with that, delivering poorer quality light. Why would I now expect a reverse of that trend? Will circadian sensitive lighting be the one thing that reverses our desire for cheap?

In one of the lectures, an audience member asked the speaker if he thought all light in the future would be circadian-regulated. He flatly stated, “No!” he gave his rationale. “We all know the typical office chair is bad for our body. Engineers have developed the quintessential solution to solve all of the problems that harm our musculoskeletal systems. How many people have purchased these chairs? Ten, twenty percent? If consumers will not purchase a more expensive chair to solve a known medical problem today, why would we think they will do so tomorrow?”

From my perspective, I want to believe lighting is much more important than a chair; but is it? I don’t suspect I’d get into a bar fight over it, but the evidence is not very compelling. Circadian lighting, like the Aeron Chain and GE Reveal lamps will appeal to a rarified population. They will be available, helpful and better, but because of the cost, ignored by the bulk of the population.