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Workplace Safety


By September 1, 2011No Comments

Some form of shift work, whether it be during the day or night, is performed by about 20% of the American workforce. Most sleep experts have concluded that working at night isn’t biologically natural for the human body. The human body has evolved to sleep during the night and participate in activity during the day. The biological processes in human cells naturally occur in a circadian rhythm. It wasn’t until the light bulb allowed us to participate in daytime activities at night that all this changed. But, this isn’t necessarily a positive change.

For some, it’s easy to change their sleep-wake schedule. Meanwhile, others find it very difficult to sleep during the day and will remain tired when they’re working at night. This is a circadian rhythm disorder called shift work disorder.

Although there is not yet conclusive data showing how many shift workers suffer from shift work disorder, research is showing that there are consequences of shift work – traffic accidents, workplace accidents, gastrointestinal illness, heart disease, and psychiatric disorders. Cancer, for example, is thought to be linked to shift work due to melatonin suppression. Melatonin is a naturally occurring hormone that is a potent antioxidant. It’s secreted in the highest amounts during nighttime sleep. So, when a person is working at night under bright lights, their body could be secreting less melatonin

Another well researched consequence of shift work is heart disease. Some studies have shown that those sleeping during the day versus at night have a tendency toward high blood pressure during sleeping hours.

Cortical rhythm, which has to do with stress reaction, and leptin levels, which helps to make a person feel full, are also altered by daytime sleeping. Some research shows that a person can increase their glucose and insulin levels and develop pre-diabetes within just a few days of sleeping during the day and working during the night. In 2007, shift work was even classified by the International Agency for Research on Cancer (a WHO subcommittee) as a probable cancer carcinogen.

Some wonder if the health affects are applicable to them if they’re a night owl or have a natural inclination to stay up late. This is being studied, but there simply isn’t a clear answer yet. In the meantime, there are some tips that anyone doing shift work can use to help minimize fatigue and insomnia.

  • Use the light to your advantage while you’re working, as light sends a signal to your brain that it’s time for the body to be awake and alert. On your drive home from work, use sunglasses or glasses that filter blue wavelength and a brimmed hat to keep out sunlight and start signaling to your body that it’s time for sleep.
  • Make your daytime sleep environment sleep friendly with blackout shades, turning the ringer off the phone, and disconnecting the doorbell. Family should understand that even though it’s daytime, this is your bedtime.
  • It may also be helpful if you don’t alter your work sleep-wake schedule too much on your days off. Of course, you still want to allow yourself daylight hours to socialize and attend to business affairs.
  • If the sleep environment and behavior changes don’t work, then you might consider melatonin. Some studies show that it’s useful for those unsuccessfully trying to sleep during the daytime. Be careful not to take the melatonin too far in advance of when you plan to sleep, as it will generally only take thirty minutes to start working.
  • Most will find help through environment and behavior changes. For those that aren’t helped by the above four tips, armodafinil / Nuvigil, a medication commonly used by those suffering from narcolepsy, has now also been approved by the FDA for shift work disorder.