WRITTEN BY DR SHELLEY JAMES
Dr Shelley James is an international lighting design consultant with specialist expertise in health and wellbeing. Shelley is also a TEDx speaker, author, WELL Light Advisory Board member and trained electrician.
Recent space station research has revealed the critical role light plays in regulating the human bodyâs internal clock. This body clock, known as the circadian rhythm, influences sleep, mood, and other physiological functions from birth through old age. Some clinicians now consider lighting a medical intervention, with one editorial even claiming that current lighting standards may violate the Hippocratic oath to “do no harm”1.
The Evolution of Lighting Technology
Until recently, lightbulbs had fixed coloursâeither cool, blue-ish light or warm, yellowish light. Dimming options were limited, and technologies like fluorescent lights could only be switched on or off. The introduction of LEDs (light-emitting diodes) has transformed lighting, offering more flexibility. LEDs can be dimmed or tuned to different colours while maintaining their lifespan. This makes them up to 80% more energy-efficient than fluorescent lights, which is crucial as energy costs rise and healthcare facilities aim for zero-carbon solutions.
Today, advanced LED systems not only offer energy savings but also gather and transmit data, helping building managers monitor occupancy, air quality, and other operational aspects.
So, What Does That Mean For The Lights?
The remarkable efficiency of LED chips and the fact that they can be dimmed or switched in a fraction of a second while maintaining their lifetime hours means that these new solutions can be up to 80% more energy efficient than fluorescents while delivering the same light levels or more.
As energy costs rise and pressure to move to zero-carbon solutions grows, many healthcare providers find they can justify the costs of an upgrade in electricity bills alone.
Increasingly, intelligent lighting systems not only deliver granular control 24/7 but have the potential to feed information back to the facilities manager or building owner, transforming the humble lightbulb into the gateway to an integrated building management system that includes occupancy rates and performance of other facilities including air quality and humidity, cleaning, and maintenance.
Helvarâs award-winning collaboration with architects JKMM and the Hospital Nova in Finland is one example of the operational benefits in action. The client, Antti Lehtinen explained: âone of the greatest benefits is having an immediate overall view of the system with Helvar Insights…so if we have letâs say a driver failure, Insights shows me exactly where it is located, which saves hours of searching time.⊠Overall, our maintenance has become more efficient with Insights, and most of it can be done before users or patients have even noticed anything,â
These energy and operational savings are substantial, but the most expensive line item for any business is its people. In healthcare, other major considerations are recovery times, medication and falls. While the âsoftâ KPIs are more challenging to measure, research suggests that lighting design, including access to controls, actively supports the diverse needs of staff and patients and can improve productivity, physical and mental health, and even reduce recruitment costs2.
Different Types of Circadian Lighting
The baseline for all circadian lighting systems are fittings known as âtunable whiteâ: these fittings include multiple chips that allow the user to shift from âcool, focusâ to âwarm, relaxedâ to suit their mood or the task in hand.
âDynamicâ lighting is programmed to shift automatically, generally from bright and cool light in the morning through to a warmer light in the late afternoon. The standard protocol can be optimised to suit âsolarâ time or activity patterns such as night shift work. This simple change has been shown to improve mood and productivity in offices and schools, especially in settings with little or no access to daylight through a window.
A subset of these dynamic lighting systems are engineered to deliver the specific levels and pattern of light-dark exposure recommended by scientists to support the day-night cycle. This is known as âcircadianâ lighting. Alongside these ambient lighting strategies, a growing number of clinics and psychiatric units, especially in Nordic countries, are using a targeted intervention known as âBright Light Therapyâ (BLT) to successfully manage depression and other mood disorders3.
Circadian Lighting in Practice
Research and real-world applications have demonstrated the value of circadian lighting. In a care home in Calgary, Canada, circadian lighting systems reduced daytime napping and improved sleep quality, which lowered the use of sedative medications4. Another large-scale project in two residential care homes found a 43% reduction in falls under circadian compared to standard lighting conditions. Another project in a specialist recovery clinic for heart attacks noted a 21% reduction in medication costs for patients with rooms on the bright side of the hospital compared to those on the darker side of the same building5.
Even in neonatal intensive care units, circadian lighting has shown benefits. Premature infants exposed to circadian lighting gained weight more quickly and were discharged earlier than those in standard lighting conditions6.
Healthcare staff also benefit from improved lighting. For night-shift workers, dynamic lighting stabilises circadian rhythms and enhances mood7, making work environments more pleasant and reducing turnover. Simple interventions, like giving staff access to dimmable switches or blue-depleted light pods, can significantly improve caregiver satisfaction and reduce patient anxiety8,9.
Itâs exciting to see a growing number of projects where integrated lighting controls are considered at the very start of the project to optimise human and environmental performance. The Intensive Care Unit at Vejle Hospital in Denmark is a great example where Helvar was involved with staff to ensure the zoning, dynamics and controls would meet their unique requirements.
Is This Reflected in Building Standards?
Healthcare lighting is governed by several building standards and regulations. While these traditionally focus on visual performance and energy efficiency, newer standards, like the EN 12464-1:2021 for office design, are beginning to account for the non-visual effects of light. Healthcare facility managers must now decide whether to stick to basic standards or embrace the latest research on circadian lighting for better outcomes.
Conclusion
Lighting, once considered just a tool to help us see and move around safely, has become a key factor in healthcare outcomes. With new insights into how light affects the body clock, and the technology to control it effectively, healthcare providers can now use lighting to improve patient care, enhance staff well-being, and reduce energy consumption. Itâs time to rethink the humble lightbulb and its hidden potential to support both human and environmental health.
1Â Cain, S. W., & Phillips, A. J. K. (2021). Do no harm: the beginning of the age of healthy hospital lighting. Sleep, 44(3). https://doi.org/10.1093/sleep/zsab016
2Hadi, K., DuBose, J. R., & Ryherd, E. (2016). Lighting and Nurses at MedicalâSurgical Units:Impact of Lighting Conditions on Nursesâ Performance and Satisfaction. HERD: Health Environments Research & Design Journal, 9(3), 17-30. https://doi.org/10.1177/1937586715603194
3Maruani, J., & Geoffroy, P. A. (2019). Bright Light as a Personalized Precision Treatment of Mood Disorders [Review]. Frontiers in Psychiatry, 10. https://doi.org/10.3389/fpsyt.2019.00085
lCirC4Constantinescu, A., Jadden, Warness, R., Virk, N., Perez, G., Shankel, M., Holroyd-Leduc, J., & Constantinescu, A. (2019). Optimizing Sleep for Residents in Long-Term Care Without Sedatives. https://www.hmpgloballearningnetwork.com/site/altc/articles/optimizing-sleep-residents-long-term-care-without-sedatives
5Walch, J. M., Rabin, B. S., Day, R., Williams, J. N., Choi, K., & Kang, J. D. (2005). The Effect of Sunlight on Postoperative Analgesic Medication Use: A Prospective Study of Patients Undergoing Spinal Surgery. Psychosomatic Medicine, 67(1), 156-163. https://doi.org/10.1097/01.psy.0000149258.42508.70
6SĂĄnchez-SĂĄnchez, M., GarcĂa, T. L., Heredia, D., ResĂ©ndiz, I., Cruz, L., Santiago, J., Rojas-Granados, A., Ubaldo-Reyes, L., PĂ©rez-Campos-Mayoral, L., PĂ©rez-Campos, E., VĂĄsquez, G. S., Moguel, J. M., Zarate, R., GarcĂa, O., SĂĄnchez, L., Torres, F., Paz, A., Elizarraras-Rivas, J., HernĂĄndez-Huerta, M. T., & Angeles-Castellanos, M. (2022). Effect of a light-darkness cycle on the body weight gain of preterm infants admitted to the neonatal intensive care unit. Sci Rep, 12(1), 17569. https://doi.org/10.1038/s41598-022-22533-1
7Lowden, A., & Kecklund, G. (2021). Considerations on how to light the night-shift. Lighting Research & Technology, 53(5), 437-452. https://doi.org/10.1177/14771535211012251
8Albala, L., Bober, T., Hale, G., Warfield, B., Collins, M. L., Merritt, Z., Steimetz, E., Nadler, S., Lev, Y., & Hanifin, J. (2019). Effect on nurse and patient experience: overnight use of blue-depleted illumination. BMJ Open Qual, 8(3), e000692. https://doi.org/10.1136/bmjoq-2019-000692
9Hadi, K., DuBose, J. R., & Ryherd, E. (2016). Lighting and Nurses at MedicalâSurgical Units:Impact of Lighting Conditions on Nursesâ Performance and Satisfaction. HERD: Health Environments Research & Design Journal, 9(3), 17-30. https://doi.org/10.1177/1937586715603194