Color tuning is often used for purely aesthetic purposes—creating lighting “scenes” or particular atmospheres. However, research suggests it could find a new home in healthcare facilities.

The Sacramento (Calif.) Municipal Utility District, the city’s ACC Care Center and the U.S. Department of Energy (DOE) partnered to explore the potential health benefits color tuning could have on residents of a senior-care facility. 


The researchers wondered how different color temperatures might affect residents’ melatonin levels. Melatonin, a naturally occurring hormone, regulates sleep and wakefulness. A person’s melatonin levels naturally rise and fall throughout the day. High levels occur at night, making a person sleepy, and levels fall during the day. 


Researchers replaced some of the ACC Care Center’s fluorescent lighting in one corridor, two resident rooms, the nurse station, the common family room and the administrator’s office with tunable white light LEDs.


Following guidelines set by the Lighting Center of Rensselaer Polytechnic Institute, researchers tuned the lights so that they were likely to suppress melatonin production from morning to midday and less likely to suppress it in the evening and at night. 


Lights in the corridor were programmed as follows: 7 a.m. to 2 p.m. at 6,500K at 66 percent output, 2 p.m. to 6 p.m. at 4,000K at 66 percent output, and 6 p.m. to 7 a.m. at 2,700K at 20 percent output.


In two resident rooms, a cove lighting system was installed with the following script: 7 a.m. to 2 p.m. at 6,000K, 2 p.m. to 
6 p.m. at 4,100K, and 6 p.m. to 8 p.m. at 2,700K. It included a 2,400K night light option from 8 p.m. to 7 a.m. and a 3,500K wall light. 


Amber LED rope lights under the bed, recessed amber LED night lights and motion-sensor lights integrated into bathroom handrails were installed so residents could navigate the room at night without overhead lighting. Amber light avoids wavelengths that make it most difficult to go back to sleep. 


In August 2016, the DOE released “Tuning the Light in Senior Care: Evaluating a Trial LED Lighting System at the ACC Care Center in Sacramento, Calif.,” a preliminary report about the project. The results documented a decrease in agitated behaviors, such as yelling and crying among three residents studied, a significant reduction in the need for psychotropic and sleep medications for one of the residents, a reduction in the number of recorded patient falls in the corridor studied, and, according to ACC staff, residents with rooms located elsewhere were now spending time in the LED-illuminated corridor. 


“The study is too small to generate unquestionable conclusions,” said David R. Errigo, National Lighting Bureau chair. “However, the study’s results seem to validate many emerging hypotheses about both natural and electric lighting’s ability to have vital impacts in healthcare facilities, especially those facilities that serve the needs of the elderly.”