Read full press release

STONEHAM, MA -----   The significant health risks linked to the use of LED lights at night may have finally been solved by an innovative new LED technology. CIRCADIAN® Light’s new Zirc™ NightSafe™ LEDs are the first lights verified by UL, the leading global safety certification company, to emit white light with less than 2% blue content at night. This medically-significant breakthrough addresses the growing scientific evidence that exposure at night to the 10 - 30% blue light content of conventional LEDs has a profound negative effect on many aspects of human health and performance.


Over the last decade numerous medical studies have identified that blue-rich light at night creates circadian disruption and health problems. The World Health Organization (WHO) and the American Medical Association (AMA) have warned that light at night is a potential carcinogen associated with an increased risk of breast cancer in women, prostate cancer in men, and gastrointestinal cancer in both men and women. The AMA further warned that the wrong light at night greatly increases the risks of mood disorders, obesity, diabetes, sleep disruption, and reproductive disorders.

By 2018 over 60 peer reviewed scientific studies had shown a significantly increased risk of breast and prostate cancers with light exposure at night. In addition, 27 major studies had shown a 25-30% increase in obesity and diabetes.

The lighting industry has believed that you cannot create white light without significant blue content. Driven by the medical necessity to remove the harmful 440-490nm blue wavelengths at night, a bio-engineering team led by Dr. Martin Moore-Ede, a former professor at Harvard Medical School and CEO of CIRCADIAN Light, in collaboration with Professor Robert Casper of Mount Sinai Hospital, Toronto spectrally engineered an innovative healthy white LED solution.

The research enabled the development of DynamicBlu™ light fixtures that utilize both Zirc™ NightSafe™ LEDs and blue-rich Day-LEDs which are precisely timed to provide the optimal 24/7 light solution. These lights have already been installed in multiple Fortune 500 companies.

“Our goal is to create lights that combine the longevity and energy efficiency of LEDs with the ideal spectrum of light by time of day, season and geographical location to entrain circadian rhythms and optimize human health and performance”, said Dr. Moore-Ede. “These lights boost alertness and productivity whenever you need it, without the circadian disruption caused by the high nocturnal sensitivity of circadian rhythms to blue light after sunset.”

“The field of circadian and human-centric lighting is expanding rapidly,” said Doros Platika MD, Executive Chairman of CIRCADIAN Light. “It was critical for us to take an evidence-based approach and test various spectra on human subjects to minimize circadian disruption. Color tuning, which involves dimming and yellowing blue-pump LED lights has been proposed as an alternative solution. But even color tuning down to 2700K still emits 8-10% harmful blue content, with 500% more blue light than CIRCADIAN's Zirc™ NightSafe™ LED technology. CIRCADIAN Lights are thus the only UL verified white light solution that meets the health target of emitting less than 2% blue.”

About CIRCADIAN Light 
CIRCADIAN Light is a company focused on the development and commercialization of innovative evidence-based LED lights that minimize circadian disruption to promote health, safety and productivity. Using spectral engineering based on medical research at the University of Toronto’s Mount Sinai Hospital, and in Boston at the CIRCADIAN Light Medical Research Center, the CIRCADIAN research and development team led by Dr. Martin Moore-Ede has produced a proprietary suite of LED products based on an extensive intellectual property portfolio. CIRCADIAN Lights have been installed in multiple leading Fortune 500 companies to reduce circadian disruption in employees and minimize the adverse health impacts of light in the evening and at night, with a resulting reduction in workforce costs including absenteeism, turnover and lost productivity.

Share this article


Circadian Light Logo