As we spring forward, is Daylight Saving Time worth it?
UBC Psychology Professor Emeritus and sleep expert Stanley Coren is the former director of the Human Neuropsychology and Perception Laboratory and author of the 1996 book Sleep Thieves. In this Q and A, Coren discusses the risks and benefits of setting our clocks one hour ahead.
What are the effects of spring Daylight Saving Time?
We live in a society that is chronically sleep-deprived, and very bad things happen when chronic sleep deprivation is an issue. Spring Daylight Saving Time is a period when a lot of people lose a little extra time.
We looked at different types of accidents, including traffic accidents and workplace accidents, in Canada and found that there was a five-to-seven per cent increase in accident fatalities during the three days following spring Daylight Saving Time. After the fall Daylight Saving Time, however, there is not always a decrease in the number of accidents because people do not always use the extra hour to sleep.
Is there anything that people can do to prepare for an upcoming time change?
Yes, go to bed earlier on the day of the change. It is harder to sleep later because humans tend to awaken fairly automatically. Our eyelids are not opaque and most people are sensitive to increases in light, so we tend to wake up before our alarms go off because of that.
Why do we have Daylight Saving Time?
The original suggestion for Daylight Saving Time came from Benjamin Franklin. He suggested that if time was adjusted so that work hours were centred during daylight, people could save money on candle wax, which was expensive. Nothing happened, however, until the First World War when resources were being taxed due to the war effort and items like oil were at a premium. Daylight Saving Time was introduced to save resources. Some countries switched the time back after the war, but when the Second World War arose there was pressure again on resources and Daylight Saving Time was reintroduced. Since then it has been adjusted and extended to optimize daylight hours.
Should we continue to use Daylight Saving Time?
There are two reasons why society continues to use Daylight Saving Time. First of all, there are energy savings across the country. The second reason is that Daylight Saving Time actually saves lives. People die during the period directly following the spring shift, but the data on traffic accidents show that accidents occur much more often during the dark or lower illumination than during daylight hours. Over the time that Daylight Saving Time is in effect people get up and return home while the highways are brighter. This occurs over a period of months, so although Daylight Saving Time causes an initial hazard, in the end there is a life-saving benefit. There is nothing that comes without its cost, and in this case the cost of saving lives in the long-term is losing lives in the short-term.
This Q and A originally appeared in UBC News on March 4, 2014.