Circadian Lighting and How It Affects Your Moods

I'm so excited to have this article on Circadian Lighting published in Northwest 50 Plus magazine!

This is a really helpful and informative article about lighting and how it affects everyday living.

You can check it out at the link below!

Northwest 50 Plus South Valley Lane County Edition November 2019

What is Circadian Lighting?

Circadian lighting is lighting that has been designed to meet our biological need for light. It promotes a healthy circadian rhythm, which helps us to be healthier and get a better night’s sleep.

For a healthy circadian rhythm and good sleep, we need both light and darkness. We need the right kind of light at the right time of the day. In contrast to our ancestors, who spent most of the day outside under dynamic and changing light, we spend most of our day indoors under static (non-changing) electrical lighting.

Using Human Centric Lighting Technology to Create Dynamic Lighting

We now have the technology to bring that dynamic outdoor lighting indoors. For healthy circadian function, we need to be exposed to blue light during the day for melatonin suppression, and no blue light in the evening for melatonin production and good sleep. Originally designed for and used by NASA, this technology has been used on space shuttles to improve the circadian rhythm of astronauts who experience many cycles of sunrise and sunset every 24 hours. Implementing this lighting gives the astronauts the lighting cues they needed for healthy circadian function, improved sleep/wake cycles, and lessens errors.

Flat panel circadian light that was used in a memory care community.

Flat panel circadian light that was used in a memory care community.

This type of lighting technology is important for all of us who spend most of our day indoors under electrical lighting. The flat panel shown here was designed specifically for an installation I did at a memory care community in Springfield, Oregon. When installed, the panel looks exactly like a sky light. In fact, you can’t tell the difference between it and the existing skylights when it’s a sunny day. It provides the residents, who spend the majority of their time indoors, with the blue-enriched light needed to properly set circadian rhythm during the first part of the day. Moving into the evening, the transition to yellow light (think about the candles and fires our ancestors used after sunset) signals the body to begin melatonin production, resulting in a better night’s sleep. This dynamic light has been shown to improve the symptoms of “sundowning”, which is a condition where the symptoms of Alzheimer’s and dementia patients worsen in the evenings. It has also been shown to improve caloric intake, decrease agitation, and improve sleep/wake cycles.

How Does Indoor Circadian Lighting Work?

These lights have a GPS beacon, that when set knows it’s exact location, and will send a signal to the fixtures every six seconds.  This will calibrate the lighting fixtures with small changes in color and intensity, to provide the dynamic light spectrum that is necessary for entrainment and a healthy circadian rhythm, these calibrations are not visible to the eye. This helps us to perform better during the day and sleep better during the night, impacting our health and well-being.

Studies have shown that the number one thing indoor workers wish they had in their workplace is more access to outdoor lighting, or better lighting inside their workspace. Installation of circadian lighting systems in the workplace can increase worker productivity and satisfaction and has also been shown to reduce the number of sick days.

How to Prevent Disruptions to Circadian Rhythm with Exposure to the Right Type of Light

Combat Jet Lag with the Journi Light


Have you ever traveled through a time-zone change and experienced jetlag? This product is designed to assist with alleviating jet lag and the symptoms associated with it. When jet- lagged, we are more prone to accidents, we make more errors, and we are more vulnerable to illness.

The Journi light is designed with the blue-to-yellow light spectrum that we need for the proper function of our circadian rhythm. When you wake up in the morning in your new location, turn on the Journi light and receive exposure to its blue light for at least 10-15 minutes. In the late afternoon, switch the light to its yellower setting. In the evening as you prepare for sleep, switch the light to its full-yellow setting, which contains no blue light at all. This signals your body to begin producing the melatonin you need for a good night’s sleep.

How Blue and Yellow light Affects Sleep

The Journi light is designed with the blue-to-yellow light spectrum that we need for the proper function of our circadian rhythm. When you wake up in the morning in your new location, turn on the Journi light and receive exposure to its blue light for at least 10-15 minutes. In the late afternoon, switch the light to its yellower setting. In the evening as you prepare for sleep, switch the light to its full-yellow setting, which contains no blue light at all. This signals your body to begin producing the melatonin you need for a good night’s sleep.

Hotel chains have decided to carry this product in some of their rooms to help their guests adjust to new time- zones after traveling. This is a great product for anyone who needs to perform well after experiencing a time-zone change, including athletes who have reported that it helps them recover faster and be in better condition to play.

Can the Daylight Savings Switch Affect Your Sleep?


We are approaching my favorite time of year for time-change, since setting our clocks back in the Fall gives us an extra hour of sleep. However, our bodies do have a natural sleep/wake cycle and anytime that it is disrupted there can be health consequences. In the Spring, when we move to Daylight Savings Time, there is a marked increase in accidents, and heart attacks. A study has even shown that judges hand down longer sentences on the Monday after Daylight Savings Time has gone into effect!

We are learning so much about how time change impacts us that as of 2021, European nations will no longer be changing their clocks to Daylight Savings Time. They will stay on one time setting for the entire year. Although we receive an extra hour of sleep in Autumn when we set our clocks back, it has been shown that we also wake earlier and can be more prone to confusion and error. 

Use Light and Sleep to Adjust to Daylight Savings Changeover

We can use light to help ourselves adjust to these changes. Try going to bed 30 minutes earlier for a couple of nights before the time change. And when you wake up, make sure to get plenty of the natural blue light in the early part of the day to set your circadian rhythm and increase alertness. When we use light in this way, it can positively affect our health and well-being and alleviate the symptoms associated with time change.

Humans and Light - The Importance of Light and the Effects of Light on People

Lumen is the Latin word for light. Element is that which is essential. So today I am going to visit with you about light that is essential for your health, well-being, and sleep.

Who am I? I was a hospice volunteer for several years and have been the owner, with my husband, of a commercial lighting company since 2008. I’m a member of the National Association of Independent Lighting Distributors, I am certified as a Lighting Specialist, I hold the Aging in Place Executive Certificate in Home Modification through the USC Leonard Davis School of Gerontology, and I am an Invited Member of the Humancentric Lighting Society which is an international society of lighting researchers, experts and neuro-scientists. I have also been the co-chair of the Walk to End Alzheimer’s for 2018-19.

I became interested in lighting based on having relatives who suffered with dementia, seeing what was happening in the lighting industry today, and wondering if lighting could have made a difference for them as they lived with that disease.

What is light?


Light is energy. Light gives energy to plants to grow. When we compare how we feel on a bright, blue, sunny day to how we feel on a gray and cloudy day it is easy to see and understand the energy we get from light, and that light is energy. Natural light is the light outside. It is dynamic and constantly changing throughout the day. Clouds go across the sun. The light changes with the seasons. In contrast, electrical light is the very same light all the time, 24 hours a day. It is static. It may be possible to dim or brighten the intensity with controls, but our bodies will always read electrical light the same way. Up until about 120 years ago, our ancestors lived under that constantly changing light that is present outside. They spent 90% of the day outside. Now, we spend 90% of our days inside under static electric light. I believe many of the health problems we are living with today can be attributed to that.

mal illumination is a lack of good light.jpg


Means lack of good light. This is similar in concept to malnutrition. We can be surrounded by food, but if we are making the wrong choices, we will still suffer from malnutrition. In the same way, we can be surrounded by light twenty-four hours a day, but if it is not the light that we biologically need at the correct time, we will suffer from mal-illumination and see the consequences in our health.

Our eyes: We have cones and rods in our eyes which help us to see color and shape in dim light. In 2002, researchers discovered IPRGC: Intrinsically Photo-Sensitive Retinal Ganglion Cells. They had known for about 80 years prior to this discovery that there was something else that our eyes were detecting.  In 2002 researchers in both the US and Europe, on the same day, announced the discovery of these cells. There is a visual component to what these cells do, but most of what they do is non-visual. These cells are photo-sensitive not only to the amount of light, but also to the color of light. They send a message through a different nervous system, down the spinal column and into the pineal gland. This is what sets our circadian rhythm.  Researchers now know that there are even more ganglion cells, and their functions have not yet been identified. But we do know that just as the cells in our ears function for both hearing and balance, the cells in our retinas are used for more than just sight. They are responsible for setting our circadian rhythm. 


Light and circadian rhythm:

Circa means about, and dia means day. So, circadian rhythm is the rhythm that repeats in about a day. Our world runs on a 24-hour cycle. However, as humans, our natural circadian rhythm is about 5-7 minutes longer than that. How many of you have ever been jet-lagged? When we are jet-lagged we are more prone to illness, accidents, falls, and poor decision-making. Can you imagine being perpetually jet-lagged and adding five to seven minutes every day? Just think how far off we would be in the course of a week, a month, or a year. This is how we can feel when our circadian rhythm is continually disrupted. Our circadian rhythm is responsible for the proper function of our hormones, heart rate, and body temperature. It is present in humans, animals, and plants. This rhythm is generated by our internal timeclock, the pineal gland that synchronizes to light and dark cycles. It is also what accounts for our waking up at the same time every day, and entrainment.

Entrainment is what happens first thing in the morning when light hits the cells in our retina.

It sets us to our 24-hour day.  This is entrainment, and it is why light is so very, very important in the morning. A healthy circadian rhythm gives us restorative sleep, lowered stress, less anxiety and depression, lower risk for cardiovascular disease and type two diabetes, lower incidence of breast and prostate cancer, and lower incidence of hormonal cancers.  Since circadian rhythm is responsible for the release of hormones, it makes sense that diseases that are the result of hormonal imbalances could potentially be caused by disrupted circadian rhythm caused by improper light. Studies have shown that nurses who work night shifts have a higher incidence of breast cancer. Researchers are finding that working under artificial light at night, not getting proper sleep, and not having a set circadian rhythm can increase the incidence of disease.

How can we have a healthy circadian rhythm?

First thing in the morning and into the early afternoon we should be exposed to bright blue light. Blue light suppresses the hormone melatonin. When we don’t have melatonin working, we have serotonin and cortisol working instead. These are our feel-good, energy, “get-going” hormones. These are what we want in the early and middle part of day. Take walks outside on lunches and breaks to get exposure to the blue light. I recommend getting outside, but we do now have humancentric lighting technology that can provide that dynamic and blue light indoors also. Both light and darkness are required for a healthy circadian rhythm. We need total darkness for good, restorative sleep. If you hold  your arm out in front of you and can still see your hand, there is too much light in the room for deep, restorative sleep to take place.

What is Humancentric Lighting and why is it important?

Humancentric lighting is lighting that is aimed at providing the right lighting for activities at the right place and time. Our ancestors lived mostly under that beautiful, outdoor, dynamic light. With the development of humancentric lighting, we can now bring that dynamic and blue light inside to our workplace and home.

The Aging Eye:

Eyes - the iris fades and weakens with age.jpg

The iris (the colored part of eye) fades as we age. The iris is also a muscle, and it controls pupil constriction and dilation. As the iris fades and weakens with age, the pupil is not dilated and constricted optimally and does not respond as well to light. Age also causes the lens of the eye to yellow and become cloudy. Think about setting a newspaper in the sun and seeing that it yellows with time. This is similar to what happens to the lens in the aging eye. These are common, normal changes to the aging eye. As a result of these changes to our eyes, we need more light to read and do tasks. Studies show that a 50-year-old needs 10 times as much light as a 10-year-old to read. A 65-year-old needs 15 times as much light as a 10-year-old to read, and a person with a vision impairment will likely need three to four times as much light as a person of the same age with no vision impairment. Dementia and diabetic retinopathy are examples of conditions that can cause vision impairments. So, if you are 65 years old and have a visual impairment in addition to a normally aging eye, you could potentially need 45 to 60 times as much light as a 10-year-old to do the same task.

My passion for light and health - especially as we age:

light and health are related- especially as we age

Much of my passion for, and interest in, light came from wanting to see how light could impact those living with dementia. A new realm of scientific studies is showing that many of the problems that affect dementia patients such as sundowning, caloric restriction due to lack of appetite, agitation, depression, and not sleeping well can be improved with exposure to blue light during the day. How many of you feel really good when you don’t get good sleep? Research has shown a reduction in agitation, falls, and depression when people are exposed to blue light at the proper time of the day, allowing them to get a better night’s sleep. Studies have shown that people in nursing facilities, if they do not have the mobility to go outside on their own, are generally only exposed to 10 minutes of blue light a day. Knowing that we need blue light for sleep and circadian rhythm, imagine being stuck inside almost 100% of the day under static, artificial light that can have such a detrimental impact on your health.

Example of circadian lighting installed at local memory care facility:

We installed under-bed lighting so residents could be checked at night without having to be disrupted by overhead lights. We installed overhead humancentric lamps that provide a very rich, blue light between the hours of 10:00am and 2:00pm. In the evening, starting at about 4:00pm, the lamps begin to change in intensity and color, eliminating the blue light and signaling the body to increase melatonin. I was with my staff for the full day of this installation, which we had prepared for and worked toward for a year. When residents were brought back into the space after the lights had been installed, three of the residents immediately said, “I feel like I’m outside”.  It was an emotional moment because it showed that there was a tangible difference, and that the residents felt better. They didn’t know why, but they knew that they felt better. We are currently in the process of upgrading four more of the houses in that facility.

Benefits of humancentric lighting:

The benefits of humancentric lighting are an entrained and healthy circadian rhythm, improved mood, and improved visual acuity. There is also a financial incentive to install humancentric lighting because since these lights are LEDs, they use less energy and provide savings on energy and maintenance costs. Studies are showing that when asked, the #1 thing that office workers wished they had was better lighting. Humancentric lighting has also been shown to improve the productivity of employees.

Humancentric lighting and sleep:

human centric lighting and sleep quality

How many of you get eight hours of sleep a night? That is what is recommended for a healthy adult. Ongoing lack of sleep or poor-quality sleep increases the risk of health problems such as diabetes, heart disease, high blood pressure, depression, and obesity. Melatonin and cortisol are hormones with opposite functions. Blue light suppresses melatonin, which is our sleep hormone, so we want to be very mindful of that in the evening when we are getting ready for sleep. We begin producing melatonin a couple of hours before we go to sleep, but this process can be interfered with if we are still being exposed to blue light that stimulates cortisol and serotonin. In the Disney movie, “Inside Out”, the story is about a little girl and how they are trying to store memories. Her memories are like bowling balls. This is very true of how our brains work. When we are in our deepest phase of sleep, we store long-term memories. It is also during this deep phase of sleep that our brain is the most active and is cleaning out the amyloid plaques that contribute to dementia and Alzheimer’s disease! I recently learned that during the day, our blood/brain barrier is more closed. Our brain is actually swollen from taking in information. At night, during our deepest phase of sleep, our brain shrinks a little bit which makes it possible for the cleaning process to take place.   If we are not getting good, deep sleep, this important process is not happening. In talking to staff in memory care facilities, I have found that they understand just how important it is to do everything possible to help residents to be able to store memory.

Getting a good night’s sleep: Exposure to blue light too close to bedtime can delay deep sleep for up to 90 minutes. We need good exposure to blue light between 10:00am and 2:00pm, and elimination of blue light as we move closer to bedtime. I wear special glasses with yellow lenses that block blue light starting a couple of hours before bed. All these things can prepare your body and brain for sleep and improve your sleep quality. Eliminate exposure to sources of blue light created by alarm clocks, TV, Smartphones, Ipads, E-readers, and night lights. Also, make sure that you sleep in total darkness.

Example of lighting’s effect on sleep:

I worked with a gentleman that had been diagnosed with circadian disruption. He had been on medication and was still having a difficult time navigating his day because of fatigue. With my Aging in Place certificate, I have developed a screening program for evaluating the lighting in homes. I went in and changed the lighting he was using in the morning and evening, and almost immediately he was able to see an improvement in his sleep and his ability to get up in the mornings and function better throughout his day.

Benefits of a good night’s sleep: Improved wound healing, improved mood, decreased risk of falls, better balance, increased cognitive function, better reaction time, hormones function better. Is there anything in this list that you are not interested in?

The Economics of Office Lighting and Why Lighting Can Improve Productivity

“Human centric lighting (HCL) is aimed at providing the right light for our activities at the right place at the right time” - Maury Wright.  


In the office setting HCL lighting will be used to create an environment that allows everyone to feel, work and be their best.  This encourages productivity, comfort and well-being because HCL is used to support the changing needs of the individual.  

There are many reasons for choosing HCL. The ability to create a comfortable environment increases productivity - and when employees are happier at work you have greater retention of talent.  The benefits of HCL include a health circadian rhythm, improved mood, greater visual acuity, improved productivity and may enable employees to sleep better at night, all with energy savings and sustainability.

So back to the 3-30-300 principle ($3 per square foot, operations/ rent $30 per square foot/ Payroll $300 per square foot)… Business owners and commercial operators can use lighting to improve efficiency in two parts of this model!  The simpler part is reducing operating costs and boosting efficiency by replacing outdated lighting with new, energy-efficient LEDs. However, the real opportunity to see gains is to use lighting as a way to boost worker productivity by using Human Centric Lighting principles.

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How is Lighting Measured & Controlled?


Light is measured in temperatures and colors, the measurement used is Kelvin (K), the warm glowing incandescent lights we grew up with are listed as 2700K, with numbers increasing as the light gets cooler.  Mid-range is 3000K-4100K and gives the look of a cool white, with a sunny day blue sky measured between 5000K-6500K being a very cool blue light. Studies have shown that the cooler light increases alertness as well as improved mood, energy and may boost productivity and sales up to 40% and creativity up to 15%! 

When we are in blue light our melatonin is suppressed, we feel energized and are more productive, we are more alert, think of how you feel on a bright sunny day.  Light sets the mood, in areas where you are wanting to increase cooperation and a sense of comfort you will want a warmer light, in production areas a brighter, bluer light is needed. 

I have had the opportunity to work with employees who have ADA’s because of the lighting in an office.  Also, I’ve worked with people who are diagnosed with circadian disruption and have trouble getting to work in the morning, others who suffer from intense eyestrain and headaches.  All have been successfully remedied with proper lighting.

Since first writing this article I have also had the opportunity to provide a tunable lighting product for a person suffering from vertigo, he is very satisfied with the results.

Why is Natural Light Important to Humans?

natural+light+modern+office+environment (2).jpg

To understand why natural light is so important, we need to think of our ancestors.  Before we had electrical light humans spent 90% of their awake hours outside. Being outside they were surrounded by natural, dynamic (constantly changing) light.  They enjoyed the warm sunrises, bright blue mid-day lighting and then the warm glow of sunsets. Once inside they had the warm light from candles or fires.  

Our biological time clock, Circadian Rhythm, is reset each day by natural lighting.  As we fast forward to today, we are spending more than 90% of our time indoors under static (non-changing) light.  A study done by UNC Kenan-Flagler Business School found that the color temperature of the light source has the most influence on how we work.  They believe that it’s in our DNA to perform better under specific lighting.

Exciting New Research on Tunable Lighting at Care Center

In April I attended LightFair, an international lighting convention that meets every year.  The newest technology is shown their as well as 4 days of classes.  This past April this was held in San Diego.  I attended numerous classes in the newly created "Healthcare" category.  One that I was especially interested in was conducted by Connie Samla from SMUD (Sacramento Municipal Utility District.  In the class she talked about a project in which the U.S. Department of Energy (DOE) was invited to participate.  This project involved a trial installation of a tunable LED lighting system in an ACC Care Center in Sacrament, CA.  The results are very exciting as the staff reported a number of health-related benefits.  These included a reduction in agitated behaviors, psychotropic and sleep medications were reduced for one of the residents, and a decrease in the number of patient falls which may be attributed at least in part to the change in lighting.  It was also reported that other residents were choosing the newly upgraded LED corridor to "hang-out" in.  

As I began Lumen Element my main question was, "what if lighting could make a difference in the lives of those living with Alzheimer's and other neuro-cognitive diseases".  This study and others that are beginning to come out support the idea that yes, lighting can have a positive impact on these individuals and others living in care communities.

To see more on this article:  click here

Sunflowers and Summer Light

It is the first of August and summer is in full bloom!  Sunflowers always make me smile and think of the beautiful days of summer.  Sunflowers reach for the sun, we could learn from them. 

I am making an effort to be outside and enjoying the sun and colorful skies as much as possible.  From my morning walks, spending time in the garden, bicycling and eating lunch and dinner outside.  I love sitting in my backyard and being entertained in the evening by the humming birds that love the flowers that I planted for them.  By being outside I am able to take advantage of the blue morning and early afternoon light as well as the yellow and reddening light in the evening.  I am sleeping better than I have in years and I contribute that to being more in sync with natural light and it’s dynamic, changing qualities throughout the day.  I have more energy throughout the day and am more productive. 

Just as the sunflower feeds my soul, I am experiencing refreshment from this wonderful world of light we are blessed to live in.


Our eyes are amazing and we now realize that they are for so much more than just vision.  In 2001 Intrinsic Photo Receptive Ganglion Cells were discovered.  In addition to the rods and cones which enable us to see colors and focus, as well as to make out shapes and contrast in dim lighting, these ipRGC’s have nothing to do with our vision. 

87% of our sensory information received is by sight, 50% of our brain is used for vision and yet within our eyes are also these ganglion cells, many of which we still don’t know what functions they perform.  We now do know that the ipRGC’s send information to the part of our brain associated with short term memory as well as our circadian rhythm.  These ganglion cells absorb light, especially blue light which is essential for the entrainment of our circadian rhythm (see blog on Circadian Rhythm). 

There is so much more to learn about our eyes and how they influence our health, with the discovery of these ipRGC’s we have gained the understanding that our eyes are essential for many of our biological functions.