Shift Workers Beware: Blue Light at the Wrong Time Can Make You Sick

shift workers LED lighting technology

Lack of Sleep Kills! It’s as simple as that. You would be amazed at the associated disease, injury, accidents, and deaths that our society is experiencing due to lack of sleep. Our “24/7” work, travel, and recreational lifestyles prove very challenging for a restful and sleep enhanced life. This is especially true for shift workers who comprise more than 20% of the primary care patient population.

Millions of Shift Workers at Risk of Circadian Rhythm Desynchronization

The term “shift work” describes regular employment outside the normal daytime hours (9am-5pm).  While most of us are sleeping soundly in our beds, there are millions of workers on shifts in the dark of night, including truck drivers, policemen and healthcare professionals.  If these folks could sleep well when their shifts end–which is when most of us are waking up–they would live longer, happier and healthier lives.  Unfortunately, that is not usually the case.

Shift workers experience misalignment between their individual sleep pattern and societal norms.  They often try to spend time with their families when they should be asleep–or simply have difficulty sleeping when they need to.  In fact, U.S. shift workers average 5-10 hours less sleep per week than non-shift workers, and this chronic sleep loss affects their health, social activities and family life.[1]

The consequences of insomnia and shift work on society and our workforce are well documented and include:

  • sleepiness
  • fatigue
  • performance decrements
  • mood disturbances
  • problems with interpersonal relationships
  • occupational difficulties
  • reduced quality of life
  • accidents, and
  • exacerbations and/or increased prevalence of chronic medical and psychiatric conditions.

Fortunately, strategies including light technologies are being developed to help improve shift-workers’ lives.

ShiftBlue Light Keeps Our Brains on High Alert

Natural sunlight, most artificial lighting, TVs, computer screens and even mobile phones contain high levels of blue light spectrum, which has a huge impact on our wakefulness.  It turns out that blue-enriched light frequencies of light keep our brains on high alert by suppressing production of the sleep hormone melatonin.  As a result, when we’re exposed to light with high levels of blue frequency, we perform at a higher cognitive level and are less likely to fall asleep.

And therein lies the problem. Blue-enriched light exposure is great for most of us during the day and for shift workers at night when they need to perform.  But blue-enriched light is bad for both shift workers and non-shift workers when they’re trying to fall asleep–no matter what time of day or night it is.

The Right Light Exposure Can Help

Controlling the light we are exposed to at certain times of day, can make a big difference in on-the-job performance, especially for those who work the night shift.  In fact, this may be the most important aspect of sleep/rest management for shift workers.  This population experiences the most dramatic circadian shift as they literally operate on an inverted day/night schedule, which is opposite of the norm for the rest of us.

In order to get better sleep, shift workers should work under blue light at night when they need to be alert and perform.  When their shift is over, continued blue light exposure is okay until a few hours before they need to go to sleep.  At that point, if light is still necessary, shift workers should switch to a light that has been scientifically-engineered to remove most of the blue light spectrum, such as the Good Night® bulb by Lighting Science.  Their brains will register the blue-depleted environment as darkness, which will help their body produce melatonin in preparation for sleep.

Other Strategies for Shift Workers

In addition to controlling the blue light exposure, other strategies may help manage fatigue and improve shift workers’ health and well-being.  These include:

  • forward (later/delayed) shifting of rotating schedules
  • optimal timing of meetings/office work involving the night shift
  • posture manipulations/exercise
  • use of pharmacologic alerting agents (e.g. caffeine)
  • reinforcing good sleep-hygiene practices, and
  • taking prophylactic or strategic naps and controlled rest breaks.

Finally, it may be a good idea to consult with a board certified Sleep Medicine Specialist to properly screen for possible sleep disorders (e.g., sleep apnea, restless leg syndrome, shift worker sleep disorder, and others).

Further development of therapeutic and operational solutions for shift workers present both a challenge–and a much needed opportunity–for society and for the medical profession.

The bottom line, light is medicine!


Light Spectrum and the International Space Station

By identifying the light frequencies that enhance our alertness, scientists have paved the way for the development of lighting technology that can either deliver or filter those “wake up” frequencies so we can stay awake or get to sleep when we need to.

In fact, this is exactly what is being deployed in the coming weeks on NASA’s International Space Station (ISS).  Our astronauts on the ISS are traveling at 17,500 miles per hour and are experiencing a sunrise and sunset every 45 minutes, which kind of makes them the ultimate shift worker.

We are excited to have light spectrum technologies aboard the ISS to help regulate our astronauts’ circadian rhythms–and look forward to future innovations in biological LED lighting.










Smith L. Johnston, III, MD, MS,

Board Certified in Aerospace Medicine from the American College of Preventive Medicine

Note: Dr. Johnston is a Medical Advisor to Lighting Science.



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