Work on a Rotating Shift? Then You Probably Have Lower Levels of Serotonin

People who work rotating shifts during the night and early morning have significantly lower levels of the hormone and neurotransmitter serotonin, according to a study of 683 men.

Serotonin plays an important role in the regulation of sleep, and low levels have been linked to:

  • Sleep problems
  • Anger
  • Depression
  • Anxiety

In the study, men who worked hours when the body typically expects to be sleeping (shifts starting at 6 p.m.) had notably lower levels of serotonin than those working shifts during the day (starting at 6 a.m.).

Anywhere from 2 percent to 5 percent of the U.S. population is thought to have sleep problems related to shift work. Shift work sleep disorder is a circadian rhythm sleep disorder that is caused by a work schedule that takes place during the normal sleep period, thereby confusing your body’s internal clock.

The disorder can result in trouble sleeping, severe fatigue, poor sleep quality, and not feeling refreshed upon waking. The ensuing fatigue can affect work performance and alertness, and may also increase your risk of getting injured at work.

Rotating shift workers typically sleep one to four hours less than average, and often feel fatigued when they’re awake.

Sleep August 1, 2007 

Science Daily August 1, 2007

Dr. Mercola's Comments:
I believe that many of you underestimate the importance of your body’s internal clock, or your circadian rhythm. This sleep/wake cycle has evolved since the beginning of time, and if you violate these very powerful biorhythms, you are asking for trouble.

Before the invention of the light bulb, it was easy to listen to and follow your circadian rhythm. You had no choice but to wake and sleep with the rise and fall of the sun if you wanted to get your work done.

Today, electric light means that you can stay up 24 hours a day, if you like, and still be productive. The temptation to burn the midnight oil can indeed be a strong one, and a 2006 study found that the two main causes why people get insufficient sleep -- and rack up a sleep debt -- were long work hours and long commutes.

Some of you, however, are working the night shift not by choice but by necessity. People in developed countries are fortunate to have access to emergency medical care, police help, and firefighters at any time, day or night.

The ones who get the short end of the stick are those who get stuck working the night shift, either because they are providing a valuable service or, perhaps, because they’ve taken on a second job trying to make ends meet.

There’s no question, though, that staying awake all night, while your body expects to be sleeping, is harmful to your health.

For example, a disrupted circadian rhythm may influence cancer progression through shifts in hormones like melatonin, which your brain makes during sleep. And, studies have linked night shift work to an increased risk of:
Further, having a lower amount of serotonin, as this study found, can easily wreak havoc with your mood.

As with most things in life, though, there ARE rare exceptions to this rule. Some people, including some of those who have commented on this article, may very well feel fine working the night shift. This may be because their bodies are strong enough, physically and mentally, to handle the disruption in the short term, however it is my strong belief that they are compromising their long-term health.

Over time, however, working the night shift is far from ideal. Yes, someone has to do it. But if it is you, I would strongly suggest trying to switch your hours, or at the very least not keeping the night shift for longer than a couple of months at a time (and giving your body a chance to readjust in between).

Anyone who is switching from a night shift to a day shift can follow these 33 secrets for getting a good night’s sleep to get their sleep schedule back on track.

Bottom Line

It is hard to argue with many thousands of years of genetic history that simply can't be overturned in a few generations because of electric lights. There are serious penalties to pay if you violate these natural laws.  The primary one is that you will simply not live out your full life expectancy.  Ayurvedic medicine has been around for about 5,000 years and chronobiology is a central element of this teaching.  They honor going to bed when the sun goes down and arising when it comes up.  India is of course, closer to the equator and doesn't have such wide swings in daylight as many of us have throughout the year, but I believe, for the most part, this is valid for most of us.

After stating my opinion though I want to emphasize that the primary rule is to listen to your body, and if it strongly tells you that violating thousands of years of human history is good for you, and you are not engaged in some sort of self serving excuse, then go for it. Your body is a great source of feedback. My experience however, is that it is very rare for most to be honestly and consistently in communication with their body's signals and that is a powerful reason why so many get sick and refuse to consider alternative strategies.
Post your comment