A train hurtled around a corner at 82 mph, eventually coming off the rails and killing four passengers. Decades earlier, faulty decision-making resulted in the deaths of the seven-person crew of the Space Shuttle Challenger. Years before these events, a stuck valve regulating the supply of coolant to a nuclear reactor nearly resulted in the meltdown of a nuclear plant in Pennsylvania.
In each of these cases, poor or inadequate sleep was one of the factors that contributed to the failure.
Even if you are not an engineer working in one of those contexts, the odds are pretty good that you occasionally get a poor night’s sleep. In fact, over one-third of American adults sleep less than the suggested minimum seven hours a night and two-thirds of American teens sleep less than their minimum recommended eight hours. Even for those with good sleep hygiene, there is one time of year when you are likely to be short on sleep – the annual shift to daylight saving time.
As an organizational psychologist at the University of Oregon, I have examined a variety of ways in which sleep affects employees. In particular, my colleagues and I investigate how circadian misalignment caused by the shift to daylight saving time leads to costly work and social outcomes.
The American public has had a love-hate relationship with daylight saving time since it first became law in 1918. But the empirical evidence for the intended benefits of daylight saving time are mixed at best, whereas the costs of the switch to daylight saving time are becoming increasingly evident.
At the crux of these costs is the effect of the time shift on our sleep patterns. When we advance the clock, our body clocks do not change so readily. It generally takes a few days for us to adapt. The upshot is that Americans sleep approximately 40 minutes less than usual on the Sunday to Monday night following the switch.
Along with my colleague, I first examined how the shift to daylight saving time affected workers in blue-collar settings. Using a database of mining injuries from the National Institute of Occupational Safety and Health, we discovered that the spring shift to daylight saving time resulted in a 6% increase in injuries and a 67% increase in workdays lost because of these injuries.
We set out to understand the effects in white-collar settings by examining how people were using their internet access on the day following the time change. By examining internet search patterns over six years in over 200 different American metro areas, we found that searches for entertainment or related categories were much more prevalent on the Monday immediately following the time change than they were on the Mondays before and after the time change. Such cyberloafing on the job following the time change suggests that people are less productive.
Based solely on the findings from our two studies, along with a study showing that the time change predicts a 5% increased incidence of heart attacks, economists estimate that the annual spring time change costs the American economy $434 million each year. Yet that is not where the costs end.
Our research has also revealed that the shift to daylight saving time influences our ability to perceive the moral features of a given situation. The time change also affects our judgment in formal settings. A recent study found that judges hand out harsher sentences the Monday following the time change.
Accumulating evidence reveals that the costs of shifting to daylight saving time cut across society. Although the negative outcomes are varied, the singular solution seems quite simple: We should change public policy. Many state legislatures have taken up this cause, with statehouses coast to coast reconsidering the annual practice. Other states could end up joining Arizona and Hawaii in abstaining from the annual daylight saving time madness.
David Wagner is an associate professor of management at the University of Oregon. Distributed by The Associated Press.