Search Results

We've got a new participant, UPRtek. They are pioneers in developing high-quality solutions for light meters, flicker frequency meters, spectrometers, and spectroradiometers. “We hope to join The Good Light Group in promoting the importance of good lighting to the world, as UPRtek's mission aligns with that of The Good Light Group. Here, there are many pioneers in the lighting industry, and we believe that good lighting also requires excellent professional measuring instruments to complement it.” Hedy Lee | Deputy Sales Manager UPRtek More info about UPRtek

Blog by Marijke Gordijn At the end of May, the Daylight Academy held its annual conference in Trondheim, Norway. About 100 participants from around the world attended the meeting and discussed the importance of daylight and how to improve human exposure to this sustainable form of light. Daylight is the natural light from the sun. It contains the full spectrum and shows a clear rhythm, with high intensities during the day to see well, but also to support our biological clock and sleep well at night. The daylight spectrum includes more than just the visible part; there are short wavelengths that are important for vitamin D production, and near-infrared wavelengths that are important for the immune system. Photo by Marijke Gordijn The Daylight Academy is a non-profit organization, initiated and funded by the Velux Stiftung. They bring together scientists from different backgrounds: architects, engineers, urban planners, sleep experts, chronobiologists and other professionals involved in daylight research or with a strong interest in daylight-related topics. Jan Denneman, chairman of the Good Light Group, became a member in 2023, Marijke Gordijn became a member at this meeting. The DLA and the GLG both have the same mission: encouraging exposure to the right light at the right time. By working together we can reach a larger audience and hope to make a real impact. In Trondheim we discussed how we can use daylight in the service of the 17 United Nations Sustainable Development Goals. We wondered why daylight is not mentioned by the European Environment Agency, while noise and clean air, for example, are. We listened to three keynote talks and participated in interdisciplinary parallel sessions. One of these sessions involved measuring northern twilight on the hotel roof at 11pm, with several participants bringing different instruments to capture the changing light. In another session we explored strategies to create more awareness among citizens about the importance of daylight. This last topic is of interest to both the Good Light Group and the Daylight Academy and hopefully we can come up with an interesting collaborative project to take this message further.

We will be sponsoring the Student Travel Award once again at the upcoming 35th meeting of our partner, the Society for Light Treatment and Biological Rhythms (SLTBR) in Prague. Last time, at the 33rd meeting, the award was won by Mushfiqul Anwar Siraji for his outstanding work on the development of a Light Exposure Behaviour Assessment. We are proud to have supported his journey. This year, we are already curious to see who will take home the Student Travel Award! More info on the 35th SLTBR meeting

The biological clock can only be synchronized with bright light during the day and dim light in the evening. Most people are unaware of the low light levels they experience indoors throughout the day. In most cases, they receive below 100 lux in their eyes, which is considered biological darkness. This is a major cause of sleep problems, lack of energy during the day, mood problems, and depressive feelings. To maintain a healthy biological clock, ensure you receive at least 500 lux in your eyes during the day. In the evening, reduce exposure to less than 10 lux, and at night, less than 1 lux. Outdoors, when the sun is up, you naturally receive thousands of lux. Indoors, you need to compensate for the lack of daylight. Sit close to a window and install bright electric lights to ensure you always receive at least 500 lux. Watch the video

William J. Schwartz, MD This study explores why different people have different reactions to light, especially how it affects their sleep-wake patterns. The research focuses on the genetic factors that influence these differences. Photo by Dewang Gupta on Unsplash Circadian Clock and Light Our circadian clock is an internal system that regulates sleep and wakefulness based on environmental light and dark cycles. Light characteristics such as wavelength, intensity, and exposure patterns help synchronize this clock to the natural day-night cycle. Chronotype Chronotype refers to individual sleep patterns, ranging from early risers ("larks") to night owls, with many variations in between. Light exposure significantly influences chronotype, but individuals react differently to the same light conditions. Biological Mechanisms Biological processes, including how our eyes process light and send signals to the brain, contribute to these individual differences. The study looks into genetic factors that might explain why people have different light sensitivities. The Study Researchers used data from 280,897 people in the UK BioBank to investigate the genetic basis of light sensitivity. They identified a new genetic locus on the ARL14EP gene, which may influence how sensitive someone is to light and could be related to retinal development. Findings People with greater light sensitivity tend to have a later chronotype, meaning they are more likely to be night owls. This might be linked to modern lighting patterns where there is less natural daylight exposure and more artificial light at night. Implications and Future Research While there are some limitations to the study, it marks a significant step toward understanding the genetic basis of light sensitivity. The ultimate goal is to develop personalized light exposure recommendations, termed "Good Light" regimens, to optimize individual circadian rhythms. This research is a promising start in understanding how genetics influence our response to light and how this affects our sleep patterns. Future work could lead to personalized advice on light exposure to improve sleep and overall health. Burns AC, Phillips AJK, Rutter MK, Saxena R, Cain SW, Lane JM. Genome-wide gene by environment study of time spent in daylight and chronotype identifies emerging genetic architecture underlying light sensitivity. Sleep, Volume 46, Issue 3, March 2023, zsac287. https://doi.org/10.1093/sleep/zsac287

Today, 16th May, we celebrate UNESCO's International Day of Light, highlighting the crucial role light plays in our health, happiness and well-being. Good light (daylight or electric light that mimics daylight) is essential for good sleep. But if you think you need darkness for better sleep quality, you are completely right. You need darkness at night. But you also need bright light during the day. Daylight is the best! Consider yourself sitting in a dimly lit room during the afternoon for around half an hour. How would you feel? •             A: Bright, active and full of attention •             B: Awake, but not very alert •             C: Sleepy, hard to keep my eyes open Did you answer not very alert, or even sleepy? So, this is what a lack of light can do to your brain! With more daytime light you feel active and you sleep better at night. So, if you want to improve your sleep, focus on the right light at the right time. Here are 4 simple rules: 1.           Go outside during daytime as much as possible 2.           Use bright light in the morning 3.           Dim your lights towards dinner 4.           Make the night as dark as possible

The International Association of Lighting Designers (IALD) is an internationally recognized organization that supports a network of 1,500 independent lighting design professionals who satisfy its rigorous qualification process. The IALD sets the global standard for lighting design excellence by promoting the advancement and recognition of professional lighting designers. Since 1969, it has advanced the lighting design profession worldwide through leadership and advocacy and serves its members by facilitating education, community, and engagement. "The International Association of Lighting Designers is honored to partner with the Good Light Group in this vital effort,” says Christopher Knowlton, Chief Executive Officer of the IALD. “Together, our organizations are deeply committed to promoting the power of quality lighting design to enhance lives and create a more sustainable future. Through this collaboration, we can amplify our vision and significantly impact the built environment to benefit all humankind."

Last week marked our 19th Good Light Group meeting. We began with a brief update on the progress of the Good Light Group by Jan Denneman. Following this presentations by Roger Sexton, Peter Raynham, and Dave Hollingsbee, concluding with a Q&A session. Research into the acceptance and effectiveness of task lighting for non-image forming effects of light A practical experiment concerning in-workplace task-lighting designed by UCL and executed by Stoane Lighting. The effect on 30 participants of using the 2022 recommendations from Brown et al on mood, alertness and sleep are explored. Roger Sexton, Stoane Lighting covered the background: why is practical in-workspace research needed to complement more disciplined laboratory research. What were the research goals and what apparatus did we make especially for it. Professor Peter Raynham, Emeritus Professor of the Lit Environment, UCL Institute for Environmental Design and Engineering (IEDE) covered his experiment design and went through the results and his analysis. Dave Hollingsbee, Managing Director Stoane Lighting showcased the product developed as a result of the research. ·        Watch the Good Light Group news. ·        Watch the introduction by Roger Sexton ·        Watch the results and analysis by Peter Raynham ·        Watch the product presentation by Dave Hollingsbee ·        Watch the Q&A

On April 16th, our group, in collaboration with the Society for Light Treatment and Biological Rhythms (SLTBR), the Daylight Academy (DLA), and Luger Research (LR), organized and presented the 'deLIGHTed Talks - Time Matters - Shining Light on Metabolic Health' lectures. Introduction Welcome, Introduction by Charna Dibner, Geneva University Charna Dibner, moderator of deLIGHTed Talks 7, provides a brief introduction of the Daylight Academy and our circadian clocks, explaining how they work, what happens if they malfunction, and how they are measured. Watch the introduction ​ From the Real World to the Lab: Why Light Matters for Metabolic Health By Kathryn Reid, Professor at Northwestern University Feinberg School of Medicine in the Division of Sleep Medicine. From the Real World to the Lab: Why Light Matters for Metabolic Health The impact of light is dependent on when it occurs relative to the internal biological clock, and as such the timing of when we get light or dark across 24-hours matters. Light exposure patterns are a modifiable factor that can have significant impact on health and wellbeing. Results from real world and laboratory-controlled studies that examine the impact of light exposure on health will be discussed. From pregnant women to older adults, data from real-world monitoring of light levels suggests that higher levels of light exposure in the few hours before and during sleep are associated with poor metabolic health. Watch this presentation ​ Diabetes in the daylight: metabolic benefits through natural office lighting? By Jan-Frieder Harmsen, since 2023, he is working as a postdoctoral researcher in the Healthy Living Spaces Lab at the University Hospital at RTWH Aachen UniversityRTWH Aachen University. Dr. Harmsen talks about a recently completed study, in which he tested if natural daylight during office hours is more beneficial for metabolic health outcomes of type 2 diabetes patients compared to constant artificial lighting. Watch this presentation ​ Panel discussion Including Q&A with the Audience Panelists: Kathryn Reid & Jan-Frieder Harmse Moderation: Charna Dibner Watch the panel discussion

Tone Elise Henriksen Tone Elise Henriksen is a Science Advisor of the Good Light Group. She works as a consultant psychiatrist at Valen Hospital and postdoctoral fellow at the Department of Research and Innovation, Fonna Health Trust, Norway. Right light at the right time is health-promoting and important for all people, but possibly even more so for people with psychiatric disorders. Light during daytime activates the brain and rest of the body at a time we are adapted to be active and awake. To seek light during the day also helps reinforce our circadian rhythms to be synchronised both internally and with the natural 24-hour light/dark cycle of the environment. Light at night promotes activity and wake when the body should rest. Also, light at night has the potential to disrupt the circadian rhythms by sending the wrong daytime signal to the brain’s master-clock. This may happen even if you are sleeping with your eyes shut. The to-date largest naturalistic study on day and night light exposure and the associations with psychiatric disorders, published in Nature Mental Health in 2023, used data from impressive 86 722 participants (from the UK biobank). The paper describes how various levels of light exposure in individuals in free-living conditions are associated with the incidence of a broad span of psychiatric disorders. The authors found that more light exposure during the night was associated with increased self-reporting of the most common and debilitating psychiatric disorders, major depressive disorder, bipolar disorder, post traumatic stress disorder (PTSD), generalized anxiety disorder, psychosis, and self-harm behavior. Higher daytime light-exposure was associated with less reported major depressive disorder, PTSD, psychosis, and self-harm behavior. Moreover, recordings of darker days and brighter nights were associated with poorer mood and well-being.  The strongest associations were found in the brightest night-time light group with a near 30% higher risk of reporting major depressive disorder and self-harm behavior. The authors also found that the day and night light conditions contributed independently and additive to the altered risks of the psychiatric disorder syndromes. Photo by Jongsun Lee on Unsplash The one-week recordings were made with a wrist-worn combined activity and light-recorder in the period 2013-2015. It is of note that the study population was on average 62 years. This means that the participants were middle-aged adults before they were exposed to LED-lights and acquired their first smartphone. After controlling for sleep quality and duration, and several lifestyle and demographic factors, the associations remained significant. Based on the data from this cross-sectional study alone, it is not possible to establish if there is a causal relationship between light exposure and the development of the disorders, whether the light exposure is a consequence of the disorders or whether there is another mediating factor. For example, patients high in anxiety such as PTSD, general anxiety disorder or psychosis may choose to sleep with the lights on, and patients with manic symptoms tend to have lights on when awake at night. However, whether cause or consequence, it is however safe to interpret that many patients reporting psychiatric disorders were exposed to unhealthy light conditions, when they should not. We know that wrong light at wrong time counteracts recovery from psychiatric disorders.  Light exposure interventions are successfully used as treatment for major depression and bipolar disorders. We also know that unhealthy light promotes weight gain, which is a risk factor for the most common cancer types and cardiovascular disorders. These somatic disorders are the main cause of the increased mortality for people with psychiatric disorders, with consistent findings of shockingly 20-25 shorter life expectancy as compared to the general population. Unlike most other known environmental factors affecting health, light conditions can be optimized with low cost and minimal risk. This study is yet another wake-up call that we should talk about light - both in the treatment context of each individual patient and at a societal level.

Our body has a daylight detector: light sensitive cells in our eyes, called “spheres”. These connect to the part of the brain called the biological clock that regulates our body’s daily rhythms. The discoverers of how the biological clock works were awarded the Nobel Prize. The daylight detector uses light to adjust our biological clock with the time of day. In the morning the intense daylight activates us. In the evening, when the sun goes down, it prepares our body for a good night’s sleep. When our biological clock is properly aligned with time we are fit during the day, our mood is upbeat and we rest well during sleep. Fact: the right light at the right time. The daylight detector needs bright light during daytime and dim light in the evening to adjust our biological clock. If you want to bring good light in your life, watch also the other steps to a healthier and happier life here: Try | Home | Good Light Group | Foundation Light supports us in everything we do. Good light means the right light at the right time. It has a great positive impact on our experience of energy, sleep, happiness and health.

16 April, 15:00 - 16:30 CEST ​ The Good Light Group, together with the Society for Light Treatment and Biological Rhythms (SLTBR), the Daylight Academy (DLA), and Luger Research (LR), are organizing and presenting the “deLIGHTed Talks” lectures. The lectures are free to join. ​ Programme ​15.00 Introduction Welcome, Introduction by Charna Dibner, Geneva University ​ 15.10 by Kathryn Reid, Northwestern University ​ 15:30 Diabetes in the daylight: metabolic benefits through natural office lighting? by Jan-Frieder Harmsen, RTWH Aachen University ​ 15:50 Panel discussion Including Q&A with the Audience Panelists: Kathryn Reid & Jan-Frieder Harmse Moderation: Charna Dibner More info