Doctors Say Cut the Lights at Night

New recommendations for street lights target health and safety

Posted Aug 22, 2016

America’s physicians recently issued a strong warning about the way we light our streets, urging limits on the use of high-intensity LED lighting at night to protect human health, safety, and sleep. Nighttime exposure to blue light is recognized as a serious hazard to healthy sleep and normal circadian function.

The American Medical Association’s (AMA) strong, new stance comes as cities and towns across the United States are switching to LED streetlights for their energy efficiency and cost savings. Roughly 10% of street lighting in the U.S. has already been converted to LED light, according to the AMA statement.

The AMA statement cites two major concerns:

  • The glare from high-intensity LED lighting poses a safety hazard for drivers at night
  • Nighttime exposure to high-intensity LED lighting negatively impacts sleep by suppressing the release of the “sleep hormone” melatonin, which subsequently disrupts circadian rhythms

It’s important to be clear: the AMA is not suggesting communities entirely reject LED lights, but recommends that communities use the lowest possible emissions of blue light in public spaces, and that LED lighting be dimmed during non-peak hours to lower human and environmental impact.

The Health Risks of Nighttime Light Exposure

The AMA is rightfully concerned about compromises to sleep and health from excessive LED streetlight exposure. Research indicates that LED streetlights, as currently designed, may be five times as disruptive to circadian rhythms and sleep patterns than traditional streetlights—but they don’t have to be.

Blue wavelength light is highly aggressive in its suppression of melatonin and disruption of circadian rhythms, the 24-hour biological rhythms that help to regulate sleep-wake cycles. The release of melatonin, sometimes referred to as the sleep hormone, is stimulated by the absence of light. When too much artificial light is present in the environment at night, melatonin levels and circadian rhythms are thrown off of their natural schedule.

Studies show that nighttime exposure to artificial light interferes with healthy, high-quality sleep. In fact, nighttime light exposure has also been linked to increased risks for many of our most common serious and chronic diseases, including cardiovascular disease, diabetes and obesity, and some cancers.

The AMA recommendations reflect the seriousness of nighttime light as a public health issue—one that communities need to take seriously when planning lighting in public spaces and transitioning to energy-efficient light sources. We live in an age of constant and abundant access to light, on a schedule that is divorced from our biological needs for darkness.

What You Can Do to Avoid Blue Light Syndrome

Returning to a simpler, darker age isn’t practical, nor is it necessary. There are a few simple steps we can all take in order to protect our health and sleep: avoid exposure to bright light, including normal household lighting, mobile devices, and television for an hour before bedtime. 

If complete darkness isn’t practical—and it probably isn’t—consider switching to lights that are scientifically engineered to emit lower—and safer—levels of blue light spectrum. Research shows that minimizing our exposure to blue light spectrum after dark, including streetlights and household lighting, is proven to support our body’s natural release of melatonin, making it easier to fall asleep—and stay asleep—longer.

Sweet dreams,
Michael J. Breus, PhD, The Sleep Doctor™

Michael J. Breus, Ph.D. is a member of Lighting Science Group’s Scientific Advisory Board. Lighting Science (OTCQB: LSCG) is a global lighting technology leader committed to improving the lives and health of people and our planet by inventing breakthrough, biologically-friendly LED lamps and lighting fixtures. The Scientific Advisory Board advises LSGC on the biological impact and commercial application of LED technology on humans, plants and animals. Find out more about Blue Light Syndrome by joining us on Facebook and Twitter: #BlueLightSyndrome