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It’s time to set clocks back for daylight savings, but what’s the point?

This weekend, millions of households will set their clocks back for the end of daylight saving time. The goal is to save energy. The results may surprise you.


We get the rituals associated with Fourth of July, Thanksgiving, and Halloween.

But before bed Saturday night, millions of households engaged in what many believe is a pointless ritual: setting clocks back one hour to end daylight saving time (officially, that happens 2 a.m. Sunday).  And, no, the point isn't to get an extra hour of sleep.  The real goal is to save energy, but does it even accomplish that? 

The European Commission recently proposed to end daylight saving time, possibly as soon as next year, believing that the practice is outdated.  It conducted a public survey that received 4.6 million replies and found 84 percent of European citizens were in favor of doing away with it. There is no similar movement in the United States, but there are still plenty of people who question the point.

First, some quick background on daylight saving time. Ben Franklin sometimes gets credit for coming up with the idea because of a 1784 essay for the Journal of Paris that suggested the French could save on the cost of candles by getting out of bed earlier to take advantage of sunshine. But the piece was satirical and he never mentioned turning clocks back or forward.

Germany became the first country to adopt the measure to save coal during World War I.  France and other countries followed suit. The United States tried daylight saving time in fits and starts beginning in 1918, but repealed it a year later. However, some states set their own daylight saving time, leading to confusion.

It wasn't until the establishment of a uniform system under the Uniform Time Act of 1966 that daylight saving time became standard.  It gained traction under the belief that electricity use inside homes would drop as people stayed outside to enjoy the later sunset. And, it was believed most people would be awake after the sun had already risen and have less need for lights.

The federal government also believed daylight saving time, which begins in spring and ends in fall, would prevent traffic crashes, as more people would travel to and from school or work during daylight.  Further, it was believed that daylight saving time would reduce crime, as more people remained outside during daylight when less crime took place.

The government liked daylight saving time so much that it decided to extend it in 2007. The start of daylight saving time was moved up to the second Sunday in March, instead of its traditional start on the first Sunday of April. In the fall, the return to standard time was moved from the last Sunday in October to the first Sunday in November, or one week later.

But no one really knew how much energy was saved during the seven-month period. So Congress asked for a study of daylight saving time's impact on national energy consumption from an expert panel. Their findings: meh. In their 2008 report, panelists concluded that the total electricity saved in the extended daylight saving time amounted to about 0.03 percent of the entire year.

"The electricity savings are small compared to the national total for the year," the report's authors wrote. They found that changes in traffic volume and gas consumption were statistically insignificant.

The study did not examine whether daylight saving time impacted children traveling to school, whether traffic accidents rose or fell, or whether it reduced crime.

Helmut Zarbl, director of Rutgers Environmental and Occupational Health Sciences Institute, is an expert in circadian rhythm — which is controlled by the timing of lightness and darkness during the day — and its influence on sleep-wake cycles. It affects hormones and sleep.

"Disruption of the circadian rhythm is a health risk," Zarbl said, noting studies showing those already at risk of a heart attack or stroke faced an even bigger risk with time changes. Other studies show that people are more groggy the day after and that rates of auto accidents go up while work productivity goes down.

Zarbl said it can take a week for a person to feel normal again. Tinkering with circadian rhythm is no small thing, he said.

"Every cell in your body has a clock and there are billions of cells," he noted. "So it's like making billions and billions of wrist watches and setting them to a different time. Every cell has a clock that runs 24 hours, but they all need to be synchronized."

Rebecca Umbach, who graduated with a doctorate from the University of Pennsylvania in May, authored a study published last year in the Journal of Experimental Criminology that examined the impact of daylight saving time on crime.  The study analyzed crime rates the day after the start of daylight saving time, and the day after the end of daylight saving time (this weekend). She thought people would be more irritable in the spring after losing an hour of sleep, a correlation borne out in previous studies, which might translate to an increase in crime.

She was wrong. From 2001 to 2014, there were actually almost 3 percent fewer assaults on the day after daylight saving time began.  Counterintuitively, she found a near 3 percent rise in assaults the day after the return to standard time.

"It's funny because people feel very strongly about daylight saving time," said Umbach. "I didn't realize that until the research received coverage in the news and people just came out of the woodwork with opinions on it."

Other studies have suggested that the sudden time shift in the spring disrupts the circadian rhythm of humans, bringing fatigue and inattentiveness. Studies have indicated a spike in car crashes and workplace injury.

In the end, though, it's hard to draw any conclusions whether daylight saving time is hurtful or whether it has real benefits.

Umbach has another hypothesis on why there are movements to do away with daylight saving time.

"I think people just get very annoyed by the inconvenience of it," she said.