Studies
Independent research and documents on the effects of light on humans
We present studies from scientific institutions around the world and results from renowned laboratories and workplaces dealing with the effects of light on the body.
✓ Eyes
A Chinese study yields new findings on cell death ferroptosis, which is found to be the underlying mechanism in blue light-induced retinal and visual damage
| Title: |
Blue light pollution causes retinal damage and degeneration by inducing ferroptosis |
| Author: | Xuan Li, Sen Zhu, Fujian Qi Lanzhou University Second Hospital, Lanzhou, School of Life Sciences, Lanzhou University & Zhongshan School of Medicine, Sun Yat-Sen University, China |
| Date: | 5. December 2022 |
✓ Eyes
Research conducted by the University of London has confirmed the therapeutic effects of around 670 nm wavelength light, which significantly slowed the decline of ageing photoreceptors in the retina of the eye.
| Title: |
Improving mitochondrial function significantly reduces the rate of age-related photoreceptor loss |
| Author: | Chrishne Sivapathasuntharam, Sohba Sivaprasad, Christopher Hogg, Glen Jeffery Institute of Ophthalmology, University College London, UK |
| Date: | 6. June 2016 |
✓ Productivity
Blue light accelerates pilots’ adaptation to night shifts
| Title: |
Using Light to Facilitate Circadian Entrainment from Day to Night Flights |
| Author: | Nita Shattuck, Panagiotis Matsangas, James Reily, Meghan McDonough, Kathleen Giles |
| Date: | 1. February 2023 |
✓ Overall health
Guide to New Building Standards and Certifications Integrating the Biological Effects of Indoor Lighting
| Title: |
Guide to New Standards for Healthy Indoor Lighting |
| Author: | Spectrasol |
| Date: | 10. April 2026 |
✓ Eyes
Red light helps with damage to vision and the retina.
| Title: |
Roles of 670 nm Photobiomodulation on Rat Anterior Ischemic Optic Neuropathy: Enhancing RGC Survival, Mitochondrial Function, and Anti-Inflammatory Response |
| Author: | Tu-Wen Chen, Yao-Tseng Wen, Pei-Kang Liu, Monir Hossen, Rong-Kung Tsai |
| Date: | 18. July 2025 |
✓ Productivity, Sleep
The Influence of Daylight on Alertness, Sleepiness, and Other Cognitive Functions
| Title: |
Relationships between light exposure and aspects of cognitive function in everyday life |
| Author: | Altug Didikoglu and others. |
| Date: | 16. December 2025 |
✓ Eyes
French research confirms the negative effects of blue and white LED light on retinal cells.
| Title: |
Repeated exposure to low doses of light induces retinal damage in vivo in a wavelength-dependent manner |
| Author: | Anaïs Françon, Laurent Jonet, Francine Behar-Cohen, Alicia Torriglia |
| Date: | 31. December 2024 |
✓ Productivity
Study on the Effects of Lighting on Circadian Rhythm and Alertness in Submarine Environments
| Title: |
Lighting as a Circadian Rhythm-Entraining and Alertness-Enhancing Stimulus in the Submarine Environment |
| Author: | Loring Crepeau, John Bullough, Mariana Figueiro, Steven Porter, Mark Rea |
| Date: | 1. January 2006 |
✓ General health
Circadian Lighting as a Measure to Prevent Patient Falls
| Title: |
The Impact of Circadian Lighting on the Incidence of Falls Among Hospitalized Patients |
| Author: | Takeshi Okinami, Toshihiro Suzuki, Nobuyuki Nishikawa, Hiromitsu Negoro |
| Date: | 14. July 2026 |
✓ Productivity, Overall health
Research Comparing the Effects of Daylight, Standard LED Lighting, and Full-Spectrum LED Lighting on Cognitive Performance and Alertness
| Title: |
Multidimensional Human Responses Under Dynamic Spectra of Daylighting and Electric Lighting |
| Author: | Yingjun Dong, Guiyi Wu, Jiaxin Shi, Qingxuan Liang, Zhipeng Cui and Peng Xue |
| Date: | 23. June 2025 |
✓ Sleep, Overall health
Dynamic Lighting Improved Attention and Performance Stability in a Simulated Space Mission
| Title: |
The effect of a dynamic lighting schedule on neurobehavioral performance during a 45-day simulated space mission |
| Author: | Leilah K. Grant, , Brianne A. Kent, Shadab A. Rahman, Melissa A. St. Hilaire, Crystal L. Kirkley, Kevin B. Gregory, Toni Clark, John P. Hanifin, Laura K. Barger, Charles A. Czeisler, George C. Brainard, Steven W. Lockley and Erin E. Flynn-Evans |
✓ Overall health
The New ISO/CIE Standard Brings Clear Guidelines for Indoor Lighting
| Title: |
ISO/CIE 8995-1:2025 – Lighting of Workplaces – Part 1: Indoor Workplaces |
| Author: | International Commission on Illumination in cooperation with International Organization for Standardization |
✓ Productivity
Light enriched with a blue component accelerated thinking, improved concentration, and increased perceived alertness in students, as demonstrated by German scientists.
| Title: |
Influence of blue-enriched classroom lighting on students׳ cognitive performance |
| Author: | Oliver Keis, Hannah Helbig, Judith Streb, Katrin Hille ZNL Transfer Center for Neuroscience and Learning, University of Ulm, Germany |
| Date: | 10. September 2025 |
✓ Eyes
Study on the impact of daylight and full-spectrum lighting on the prevention of myopia in children and adolescents
| Title: |
Myopia and daylight - A combination of factors |
| Author: | Hobday, R. H., Aarts, M. A., Cajochen, C. C., Maierova, L. M., Münch, M. M., et al. |
| Date: | 2. July 2025 |
✓ Productivity, Mood, Sleep, Overall health
Artificial Lighting and Its Impact on the Life and Health of the Czech Population
| Title: |
Czechs and Light |
| Author: | PerfectCrowd Company |
| Date: | 28. January 2026 |
✓ Overall health
The new American national standard ANSI/IES RP-46-23 highlights the need to consider the biological effects of light when lighting interiors
| Title: |
ANSI/IES RP4623 (Recommended Practice: Supporting the Physiological and Behavioral Effects of Lighting in Interior Daytime Environments) |
| Author: | Illuminating Engineering Society (IES) |
| Date: | 17. December 2025 |
✓ Overall health
The Dentled study on the impact of full-spectrum lighting on health, cognitive function, and psychological well-being in dental clinics
| Title: |
Studie o zdravotních přínosech osvětlení s plným spektrem |
| Author: | Partonen, T., Cajochen, C., Vandewalle, G. a kol. |
| Date: | 23. May 2024 |
✓ Overall health
The effect of light on sleep quality, stress levels, healing speed, medical errors and length of hospital stay at The Vesey Hospital in the UK
| Title: |
Lighting’s Impact on Patient Wellbeing: Insights from The Vesey |
| Author: | Dr. Natalie Summers, The Vesey Research Institute |
| Date: | 17. October 2025 |
✓ Overall health
An American study in collaboration with Apple confirms: more light = less stress
| Title: |
Summer Glow: How much daylight are Apple Heart and Movement Study participants getting and why does it matter? |
| Author: | Calum MacRae, Angela Spillane, Courtney Smith, James Truslow, Diana Nascimben, Kat Cyr, Huiming Lin, Shinichi Goto, Fanual Berhe, Hannah Keough |
| Date: | 20. October 2025 |
✓ Overall health
A South Korean study confirmed the positive effects of natural daylight on the length of patient hospitalization.
| Title: |
The Effects of Natural Daylight on Length of Hospital Stay |
| Author: | Man Young Park, Choul-Gyun Chai, Hae-Kyung Lee, Hani Moon, Jai Sung Noh Korea Institute of Oriental Medicine, Architectural Environment Research Institute, Kwangwoon University, Seoul, Korea, Ajou University, Suwon, Korea |
| Date: | 14. September 2025 |
✓ Overall health
In Germany, as of August 2025, the DIN 5031-100 standard became a key guideline for the application and assessment of the non-visual properties and effects of electric light on humans in building interiors.
| Title: |
DIN 5031-100 |
| Author: | Working Committee NA 058-00-27 AA “Effects of Light on Humans” at the DIN Standardization Committee for Lighting Technology (FNL) |
| Date: | 10. September 2025 |
✓ Overall health
Disruption of circadian rhythms has been identified by the World Health Organization (WHO) as an independent risk factor for cancer. A paper by American scientists outlines the main regulatory functions of the circadian rhythm and its relevance to the development and treatment of cancer.
| Title: |
Cancer and the Circadian Clock |
| Author: | Ayesha A. Shafi, Karen E. Knudsen Thomas Jefferson University, Philadelphia, Pennsylvania |
| Date: | 1. August 2019 |
✓ Sleep
Blue light at bedtime and at night disrupts the sleep cycle by suppressing melatonin release and shifting circadian rhythms, leading to health problems such as increased risk of dementia, diabetes and heart disease.
| Title: |
National Geographic: About sleep and light |
| Author: | Michael Finkel National Geographic |
| Date: | 15. August 2018 |
✓ Sleep
Research from Shanghai’s Fu-tan University investigating the effect of indoor LED lighting has shown that sufficient light with high biological efficiency during the day leads to higher daytime whiteness and night-time sleep quality.
| Title: |
Influence of the spectrum of all-day LED lighting on human daytime and night-time performance |
| Author: | Nuoyi Li, Sicong Zhou, Wenqing Miao, Congshan Dai, Ali Hassan Shah, Yandan Lin School of Information Science and Engineering, Fudan University, Shanghai, China |
| Date: | 15. February 2023 |
✓ Sleep
A paper by the US National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) confirms that increasing light exposure at undesirable times and reducing the dynamic range of light between day and night has had negative consequences for human health in relation to melatonin production.
| Title: |
The Complex Effects of Light on Metabolism in Humans |
| Author: | Asuka Ishihara, Amber B. Courville and Kong Y. Chen National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, USA |
| Date: | 14. March 2023 |
✓ Eyes
Experimental research conducted by China’s Tianjin Medical University has shown that prolonged exposure to harmful blue light causes changes on the surface of the eyes that manifest as dry eye syndrome and also increases the risk of eye inflammation.
| Title: |
Influence of Light-Emitting Diode-Derived Blue Light Overexposure on Rat Ocular Surface |
| Author: | Li Nan, Yifan Zhang, Hui Song, Yan Ye, Zhixin Jiang and Shujun Zhao Tianjin Eye Hospital, Tianjin Key Lab of Ophthalmology and Visual Science, Nankai University Affiliated Eye Hospital, Clinical College of Ophthalmology Tianjin Medical University Tianjin Eye Institute, Tianjin, China NHC Key Laboratory of Hormones and Development, Tianjin Key Laboratory of Metabolic Diseases, Chu Hsien-I Memorial Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, China |
| Date: | 10. January 2023 |
✓ Eyes
Research conducted by China’s Zhejiang University has confirmed that prolonged exposure to harmful blue light significantly damages the retina of the eye, including disrupting mitochondrial function and increasing the risk of macular degeneration.
| Title: |
Long-term blue light exposure impairs mitochondrial dynamics in the retina in light-induced retinal degeneration in vivo and in vitro |
| Author: | Liyin Wang, Xin Yu, Dongyan Zhang, Yingying Wen, Liyue Zhang, Yutong Xia, Jinbo Chen, Chen Xie, Hong Zhu, Jianping Tong, Ye Shen Department of Ophthalmology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China Clinical Research Center, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China Department of Ophthalmology, Shaoxing Central Hospital, Shaoxing, China |
| Date: | 24. January 2023 |
✓ Eyes
A study by Polish and Ukrainian universities confirms that exposure to harmful blue light at even low intensities reduces melanopsin production and damages mitochondria in the inner photosensitive ganglion cells of the retina. Therefore, it is desirable to reduce harmful blue light in long-term light sources, in order to maintain both proper circadian rhythm functions and eye health.
| Title: |
Low-Intensity Blue Light Exposure Reduces Melanopsin Expression in Intrinsically Photosensitive Retinal Ganglion Cells and Damages Mitochondria in Retinal Ganglion Cells in Wistar Rats |
| Author: | Natalia Ziółkowska, Bogdan Lewczuk, Natalia Szyryńska, Aleksandra Rawicka and Alla Vyniarska Department of Histology and Embryology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Poland Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Stepan Gzhytskyi National University of Veterinary and Biotechnologies, Ukraine |
| Date: | 23. March 2023 |
✓ Productivity
Team of University of Illinois researchers confirms effects of light on mental function, alertness and health of students and office workers
| Title: |
Natural Light and Productivity: Analyzing the Impacts of Daylighting on Students’ and Workers’ Health and Alertness |
| Author: | N. Shishegar, M. Boubekri Illinois School of Architecture, University of Illinois at Urbana-Champaign, USA |
| Date: | 15. April 2016 |
✓ Productivity
Extensive US research has found a significant positive effect of natural daylight on the performance of primary school pupils. The improvement was by 15-26% in math and reading.
| Title: |
Daylighting in Schools – An Investigation into the Relationship Between Daylighting and Human Performance |
| Author: | Lisa Heschong The Pacific Gas and Electric Company, California Board for Energy Efficiency Third Party Program |
| Date: | 20. August 1999 |
