How do you convince an industry that their top selling products have a serious health problem documented in over 20,000 scientific studies? Over 99% of lights sold today emit excessive amounts of blue light in the evening, disrupting circadian clocks and causing an increased risk of health problems, including obesity, diabetes, and breast cancer.
The lighting industry claims the science is not yet sufficiently mature to build into lights. But do the scientists who have done this research agree?
To find out we invited all the leading scientists researching circadian rhythms and light to participate. 248 of these scientists, who had published a total of 2,697 peer-reviewed publications on light and circadian clocks since 2008, completed an online survey with 40 potential consensus statements. The Circadian Light Consensus study, released as a pre-print while being peer-reviewed for publication, shows that consensus was established for 24 of these statements, including:
- Light used in the evening (during the three hours before bedtime) should have as little blue content as practically possible.
- LED lights with high 460-495nm blue content should carry the warning label “may be harmful if used at night.”
- There is now sufficient evidence to support the widespread introduction of circadian lighting that adjusts light intensity and blue content across day and night to maintain robust circadian entrainment and health.
The lighting industry has had a bonanza decade selling energy-efficient blue-enriched LED lights – climbing from 1% share in 2013 to over 80% share of the lighting market in 2023. Along the way LED lighting sales have been boosted by government regulations and energy policies banning incandescent, halogen, CCFL and now fluorescent lights.
But now the medical evidence has caught up with the blue-pump LED revolution. It is time to readjust the LED spectrum to only provide blue rich light in the daytime, and remove the blue out of light at night. This circadian LED lighting technology has been fully developed and proven in real world applications over the past 5-years. The lighting industry needs to promptly make the switch to circadian blue modulated light to support health and avoid unnecessary illness and disease.