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The science is extensive, and the risks well established, yet most people are largely unaware of the risks to their health from artificial LED and fluorescent lights. Ultimately it is up to each of us to demand healthy circadian lighting. Don’t leave your lighting decisions to your local hardware store, or to electricians and building maintenance, or to a corporate sustainability executive who is paid bonuses solely for energy-savings goals. You need to know the real story and understand the impact of the wrong versus right lights on you and your loved ones.

My groundbreaking book THE LIGHT DOCTOR, and my regular Substack newsletter arm you with the facts and the knowledge you need to make one of the most basic decisions about your health – as basic as the food you eat and the air you breathe. This book tells you how to find and install the lights that will make your home a healthy haven, and how to become an advocate for healthy lighting in your workplace, schools, hospitals, senior living homes, and retail stores.

We don’t have to give up electric light. But we need to get healthier by using electric lights that are sky blue-rich during the day and blue-depleted at night. Because less than 0.5 % of lights sold today meet this standard, the rates of diabetes, heart disease, and cancer are climbing. There is no good reason why young nurses working night shifts should continue to have a 40% increased risk of breast cancer. There is no good reason why obesity, sleep disorders, and fatigue should continue to be an international epidemic.

I bring you a unique perspective from the forefront of the battle against unhealthy lights. While a professor at Harvard Medical School, I discovered the location of the circadian clock in the human brain and how it is synchronized by light. As a consultant to over 50% of the Fortune 500 companies, I have seen first-hand the harmful effects of light at night in the real world. My discovery of the narrow sky-blue signal that synchronizes circadian clocks led to the invention and patenting of evidence-based circadian lighting and the demonstration of its effectiveness in many major companies. The circadian lights that my team and I developed are already installed in the safety-critical workplaces of over 50 Fortune 500 companies with documented improvements in workforce alertness and health.

THE LIGHT DOCTOR explains the barriers to healthy lighting. One problem is the lack of communication about harmful lighting from scientists. As one industry leader said about circadian lighting, “Nobody knows about it … Scientists know, but they only talk to each other. If you talk to your neighbor, they won’t know.” This book breaks through this lack of communication to provide you with the critical knowledge on how to choose safe and healthy lights, which are readily available to everyone.

About the Author

For over 40 years, Dr. Moore-Ede has been a leading world expert on circadian clocks and the health problems caused by electric light at night. As a professor at Harvard Medical School (1975 – 1998), he led the team that located the suprachiasmatic nucleus, the biological clock in the human brain that controls the timing of sleep and wake, and pioneered research on how circadian clocks regulate the timing of body functions. His book, The Clocks That Time Us: Physiology of the Circadian Timing System (Harvard University Press), became the leading textbook in hundreds of college courses.

In 1983 Dr Moore-Ede founded the global consulting and technology firm, CIRCADIAN® (https://www.circadian.com/) with offices in Boston, London, Amsterdam, Osaka, and Brisbane which applies circadian physiology to improve 24/7 workforce productivity, health, and safety to clients that include over half of the Fortune 500. His experience in applying circadian science to 24/7 industry is described in his international best-selling book, The Twenty-Four Hour Society: Understanding Human Limits in a World That Never Stops (USA and Canada edition: Addison-Wesley, 1993, UK edition: Piatkus Books; German edition: Wilhelm Heyne Verlag; Australian and New Zealand edition: Random House Australia; Japanese edition: Kodansha; Chinese edition: China Times Publishing Co).

To address his clients’ growing concerns about the harmful effects of conventional fluorescent and LED lighting on workforce health, safety, and performance, Dr Moore-Ede founded the Circadian Light Research Center in 2010 and spun off the tech start-up CIRCADIAN ZircLight in 2011.  He led the team that identified the key blue signal that synchronizes circadian clocks, and developed patented LED lights, which provide circadian optimized light across day and night based on comprehensive medical research. For more than 5 years the effectiveness of these circadian-modulated lights has been validated by installing them in the 24-hour operations of Fortune 500 companies and hospitals. To make this technology more widely available, the proprietary IP portfolio and lighting assets of CIRCADIAN ZircLight were acquired by Korrus in 2022 and licensed to several leading lighting companies.

Dr. Moore-Ede graduated with a First Class Honors degree in Physiology from the University of London, received his medical degrees from Guy’s Hospital Medical School, and his Ph.D. in Physiology from Harvard University. He has published 10 books and more than 180 scientific papers on the physiology of the circadian system, interaction with environmental light, and the consequences of circadian disruption including human fatigue, errors and accidents. Dr. Moore-Ede holds multiple patents on assessing and mitigating circadian disruption and fatigue.

Moore-Ede has served on multiple national and international committees and has received numerous awards including the Bowditch Lectureship of the American Physiological Society. He is a frequent guest on television (CNN, Today Show, Good Morning America, 20:20, Dateline, Oprah Winfrey, Nova, BBC), radio (NPR Fresh Air, Connection), and print media (Wall Street Journal, New York Times, Washington Post, Time and Newsweek). He has testified before Congressional committees on multiple occasions and advised government agencies on the health and safety of the 24/7 workforce in the US, Canada and Europe.

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The light we see is as important to our health as the air we breathe, the food we eat, and the water we drink. THE LIGHT DOCTOR shows you how to take charge of the light you see and avoid using harmful and unhealthy LED and fluorescent light.


Leading expert for 40 years on circadian clocks and the circadian disruption & health problems caused by LED light at night & prevented by circadian light. See THE LIGHT DOCTOR: Science & Solutions for Replacing Your Lights Now to Protect Your Health