

By Avital Andrews

Maintaining a regular circadian rhythm is crucial for human health. But almost 15 percent of full-time salaried workers in the United States work the graveyard shift, making them susceptible to sleep-cycle issues that, according to a new study, “can jeopardize occupational health and safety by causing human errors and changes in basic biological and physiological functions.”

Whether it's an emergency room doctor, a security guard, or a night editor, a person working odd hours is 30 percent more likely to fall asleep on the job or have insomnia than a day-working counterpart. That problem, called “shift-work sleep disorder,” inspired a team of international researchers (the majority of them in Finland, land of the midnight sun) to figure out whether there's something these groggy employees can take to perk up -- without a lot of side effects.

To conduct their study, published last week in the Cochrane Database of Systematic Reviews, the researchers surveyed 15 existing experiments that used “pharmacological” interventions, like caffeine and melatonin, on a total of 718 people who work unconventional hours. All of these previous papers looked into substances that “prevent drowsiness or improve alertness during shift work” as well as those that “improve sleep quality or sleep length.”

After analyzing other researchers' work on the matter, the team concluded that more research needs to be done.

“There is low-quality evidence that melatonin improves sleep length after a night shift but not other sleep quality parameters,” they wrote. “Both modafinil and armodafinil increase alertness and reduce sleepiness to some extent … but they are associated with adverse events. Caffeine plus naps reduces sleepiness during the night shift, but the quality of evidence is low.” Finally, the paper came to this: “Both sleep and alertness promoting agents have potentially serious adverse effects. Therefore, we need more trials to determine the beneficial and harmful effects of these drugs.”

Overall, the authors found that both over-the-counter and prescription medications are largely useless for bleary-eyed shift workers trying to overcome the consequences of working odd hours -- and that in some cases, popping a pill does more harm than good.