With the 2018 Strategies Unlimited LED market forecast reporting that global indoor luminaire revenue alone will represent over $70 billion by 2022, the solid-state lighting (SSL) industry is experience massive growth on a national and global scale, with significant traction in human-centric applications. Although current LED lighting has unprecedented energy efficiency, we’re still illuminating our homes with more light at night. These bright light signals at night play a major role in our mental and physical health, as light is the key synchronizer of circadian rhythm. As a result, there’s been an industry shift to developing circadian LED lighting to account for the immense impact light has on physiology.
While the lighting design community heavily embraced circadian lighting in 2018, most of these human-centric lighting designs will not be implemented until this year, or the next. Thus, 2019 will be a transformative year for circadian lighting as it addresses the following three trends.
The end of skepticism
The biggest challenge with circadian lighting traditionally is skepticism. Lighting overall is highly undervalued, from both a design standpoint and a biological effects standpoint. Luckily, there is culminated evidence that circadian disruption leads to a whole host of increased health risks, such as risk of Type 2 diabetes, cardiovascular disease, metabolic disease, and mental health issues such as attention deficit disorders, insomnia, bipolar disorder and depression.1–4 With a growing understanding that the effects of circadian disruption are more prevalent in today’s society because of our time indoors, designers, manufacturers, and consumers alike are starting to realize that our indoor environment is not providing the benefits we need.
Social jet lag
A recent study shows5 that more than 87% of standard-day working people (9:00 AM–5:00 PM) have some form of “social jet lag,” a term used to describe the issues that arise from irregular sleeping patterns including fatigue, psychological stress, and poor health. In the next year, social jet lag will be exacerbated by the fact that current LED spectra can stimulate nonvisual photoreceptors, which will in turn further expose us to physiological risks when we spend time in poorly-lit or overly-bright settings (bars, concerts, movie theaters, etc.). It is tremendously important to focus on the sky-blue photoreceptor specifically in an effort to combat social jet lag and help create environments that positively impact our mental and physical health.
Preventing the domino effect
Once implemented, circadian lighting can positively change our mood, energy levels, and overall wellbeing. But those who overlook the value of lighting can tip the first domino into circadian dysfunction, which comes with a myriad of consequences. If unaddressed, short-term consequences that we’d see from poor lighting include increased fatigue, inability to concentrate or focus, difficulty retaining information, poor nighttime sleep, and increased appetite. The long-term consequences of continuing to work or live under poor lighting could be more severe. As previously mentioned, this includes increased risk of Type 2 diabetes, metabolic issues, cardiovascular issues, attention deficits, insomnia, bipolar disorder and certain cancers.
With further research that continues to expose the physiological impact of lighting, the increased prevalence of social jet lag, and urgency to resolve interrelated health conditions, LED lighting will have to balance energy efficiency with biological impact. I believe the next wave of lighting technology will focus on integrating energy efficiency with spectrum optimization for better human-centric lighting design. And, technology will continue to follow scientific findings that expose the impact of poor lighting. In five years, expect to see lights automatically adjust to individual biological needs in real time and bring us into a new phase of circadian lighting.
1. S. Reutrakul and K.L. Knutson, “Consequences of circadian disruption on cardiometabolic health,” Sleep Med. Clin. 10, 455–468, 2015.
2. T. Roenneberg, K.V. Allebrandt, M. Merrow, and C. Vetter, “Social jetlag and obesity,” Curr. Biol. 22, 939–943, 2012.
3. A.V. Nedeltcheva and F.A. Scheer, “Metabolic effects of sleep disruption, links to obesity and diabetes,” Curr. Opin. Endocrinol. Diabetes Obes. 21, 293–298, 2014.
4. P.M. Wong, B.P. Hasler, T.W. Kamarck, M.F. Muldoon, and S.B. Manuck, “Social jetlag, chronotype, and cardiometabolic risk,” J. Clin. Endocrinol. and Metabolism 100 (12), 4612–4620, 2015.
5. T. Roenneberg and M. Merrow, “The circadian clock and human health,” Curr. Biol. 26(10), R432–R443, 2016.