12 Surprising Effects of Daylight Saving Time

bee32/iStock via Getty Images
bee32/iStock via Getty Images

Every March, clocks "spring forward" across much of the United States, robbing people of one precious hour of sleep. In November, those same clocks "fall back," giving them 60 extra minutes of shut-eye. While hearing people complain about missed alarm clocks is one not-so-surprising effect of Daylight Saving Time, the possibility of a longer prison sentence for those going before a judge on "sleepy Monday" is less expected. Here are 12 surprising effects of Daylight Saving Time—the good, the bad, and the scientifically ambiguous.

1. Increased Spending

Woman whips out her credit card while hanging out on a hammock
iStock.com/martin-dm

In 2016, JP Morgan Chase decided to look into the economic consequences of Daylight Saving Time (DST) by examining Los Angeles and Phoenix, two cities that are large, relatively close to each other, and have stable weather. Critically, Phoenix doesn't observe DST while Los Angeles does [PDF].

Among their findings, DST was "associated with a 0.9 percent increase in daily card spending per capita in Los Angeles at the beginning of DST." Perhaps more surprising, the end of DST was associated with a per capita daily spending reduction of 3.9 percent.

2. A Higher Risk of Heart Attacks

An image of a man grabbing his chest.
iStock.com/PeopleImages

Many studies have shown that DST is associated with an increase in heart attacks, with one study showing a 24 percent increase in the number of heart attacks on the Monday after DST at a group of Michigan hospitals. According to the University of Michigan, Mondays are bad for heart attacks in general (researchers believes the stress of beginning a new workweek and changes to the sleep-wake cycle are the reason why), but DST makes everything worse. Interestingly, the Tuesday following the end of DST was associated with a 21 percent drop in patients.

3. Missed Appointments

Young man runs to catch a missed train
iStock.com/Drazen_

Somewhat relatedly, a 2017 study found that the percentage of missed medical appointments increased significantly following DST. But as with heart attack risk, the missed appointments decreased in the fall—at least temporarily.

4. More Car Accidents … Maybe (at Least for a Few Days)

An image of a car with a broken headline after being in an accident.
iStock.com/CHRISsadowski

Another field where studies aren't as consistent as one might expect is traffic accidents. In 2001, an American study found that there was a significant increase in accidents on the Monday after the shift to DST. A 2018 New Zealand study echoed the sentiment, finding that on the first day of DST road accidents increased 16 percent. In contrast, a Swedish study found that DST didn't have any important effect in that country.

Of course, there's more to DST than just those first couple days. After DST has gotten started, there's more light on the road later in the day. Several studies have found this light reduces accidents substantially, so much so that one study concluded that a year-round DST would reduce motor vehicle occupant fatalities by 195 per year.

It's so complicated that a 2010 analysis in Minnesota listed 10 studies that found positive effects of DST on road safety, and six studies that showed negative effects in both the spring and fall changes.

5. Longer Prison Sentences

A photo of a judge handing out a sentence with a clock sitting next to her
ISTOCK.COM/TZAHIV

Researchers frequently use DST to study sleep deprivation in populations, as it's a period of time when we all wake up an hour before we’re used to. One of these studies focused specifically on judicial punishment in U.S. federal courts. The researchers looked at "sleepy Monday" (the Monday after the time change) and compared the sentence lengths to other Mondays. They found that on "sleepy Monday," judges handed out 5 percent longer sentences. But don't think you can get a lighter sentence during the fall switch; the researchers found no effect on sentencing at that time. But the researchers point out that this probably isn't limited to judges—even managers may find themselves in the mood for doling out harsher punishments.

6. More Mining Injuries

An image of mining helmets on a shelf.
iStock.com/dannyfroese

According to one study of mining injuries from 1983 to 2006, the Monday directly after the switch to DST was associated with 5.7 percent more workplace injuries and 68 percent more workdays lost because of injuries, indicating that there are more injuries that are more severe after the switch [PDF]. There isn't, however, a corresponding decrease in the fall.

7. Fewer Koala Collisions

A street sign warns of koala bears
iStock.com/hidesy

One study decided to look at how DST affected human-wildlife interaction, specifically koala-vehicle collisions [PDF]. Because koalas are largely nocturnal, they often cross the road in the evening or at night. By shifting traffic patterns to times when it wasn't dark, the researchers found that DST could "decrease collisions with koalas by 8 percent on weekdays and 11 percent at weekends" (although the difference between weekend and weekdays wasn't significant, the researchers proposed that a slight increase in morning collisions lessened the benefit during the weekday). The researchers hope that further study can be done on human-animal interactions and DST.

Koalas aren't the only ones crossing a road that benefit from DST; pedestrians might be safer as well. One study found "no significant detrimental effect on automobile crashes in the short run" and in the long run was associated with "a 8 to 11 percent fall in crashes involving pedestrians … in the weeks after the spring shift to DST." Meanwhile, another study found that a year-long DST would mean 171 fewer pedestrian fatalities a year.

8. Decreased Satisfaction With Life in General (and Increased Use of the Word Tired)

A woman sitting in front of a computer looking tired.
istock.com/PeopleImages

In both the UK and Germany, studies have shown that life satisfaction deteriorates in the first week after the switch to DST in the spring. One study even quantified the deterioration in Germany with money. For the entire sample, the cost was calculated to be €213 (about $262), but for people in full employment—with relatively inflexible schedules—that increases to €332 ($408). And for the men in the sample, the cost of transition was €396 ($487).

Meanwhile, a Facebook analysis looked at the "feelings" people were sharing on the platform. On the Monday after the start of DST, the use of the word tired increased by 25 percent, with similar increases for "sleepy" and "exhausted" (as well as "wonderful" and "great"). In just the period from 5 a.m. to 12 p.m. on Monday, "feeling tired" usage increased an average of 86 percent, from a 12 percent increase in the non-DST Arizona up to a 231 percent increase in Delaware. By Thursday, "tired" is back to normal.

9. Sleepier Kids (Maybe)

A little girl sleeping with her mouth open.
iStock.com/quintanilla

The studies surrounding DST and school children are surprisingly inconclusive. On the one side, a 2009 article in Sleep Medicine looked at 469 Germans from 10 to 20 years old and divided them up into 'larks' (those who go to bed early and wake up early) and 'owls' (those who go to bed late and wake up late). They found that after the DST transition the group was sleepier for three weeks after the transition, with owls showing higher daytime sleepiness, and proposed that tests shouldn't take place in the week following the switch over to DST.

A 2017 article in Economics of Education Review, however, looked at 22,000 Europeans students and found that, at least for low-stakes tests, the effect wasn't statistically significant.

10. More Cyberloafing on the Job

A woman gets caught cyberloafing at work
iStock.com/Manuel-F-O

Another study looked at people's Google search trends for the Mondays before the switch to DST, immediately after the switch, and a week after, with a specific focus on sites like Facebook, YouTube, and ESPN (i.e. entertainment sites that people probably aren't Googling for their jobs). They found that on the Monday after the switch, people searched for 3.1 percent more entertainment websites than the Monday before DST, and 6.4 percent more than the subsequent Monday. While the researchers caution they can't be sure this was all "cyberloafing," the fact that there was nothing else special about these Mondays meant it very likely was.

11. Mistimed Insulin Shots

A woman injecting herself with an insulin pen.
iStock.com/6okean

It might seem that in this age of smartphones and connected devices that figure it all out, the twice-yearly ritual of finding all the clocks to change is a thing of the past. But that's not necessarily true. In a 2014 article in the Journal of Diabetes Science and Technology, the authors pointed out an easy clock to miss: insulin pumps. Because most commercial pumps aren't GPS-enabled and lack internal time change mechanisms, they have to be manually set up. The study authors discuss an international college student with an insulin pump that came from a country that didn't observe DST, meaning the clock was an hour off. They say that no significant harm resulted, but it just serves as a reminder to make sure you check all your clocks.

12. Higher Energy Bills

Man reviews an energy bill on a tablet app
iStock.com/baloon111

One of the main rallying cries for DST is that it saves energy, but studies have been mixed. In 1975 the Department of Transportation issued a report about whether a short-lived, year-long DST experiment had been worthwhile [PDF]. They declared "modest overall benefits might be realized by a shift from the historic six-month DST system," but cautioned that these benefits were difficult to isolate. Optimistically, though, they said DST might help reduce 1 percent of electricity use.

But as modern researchers have noted, electricity usage has shifted since then. Chief among the changes: Only 46 percent of the new single family households completed in 1975 had air conditioning, compared to 93 percent in 2016 [PDF].

Indiana provided a good place to test this change, because in 2006 they decided to observe DST as an entire state (individual counties had observed DST before). A study ultimately concluded that while DST does save electricity in lighting, this is more than offset by increased demands for heating and cooling, resulting in Indiana households being hit by $9 million per year in higher electricity bills [PDF]. However, the study only looked at residential electricity consumption, not commercial or industrial.

Around the same time, the Department of Energy also looked into DST and found that during a four-week extension, electricity use decreased about half a percentage point per day. Ultimately, Stanton Hadley at the Oak Ridge National Laboratory told Live Science, "I could see the answer being either way."

This story originally ran in 2018.

10 Surprising Facts About Wham!’s 'Last Christmas'

Michael Putland/Getty Images
Michael Putland/Getty Images

Over the course of his illustrious career, George Michael gave the world many gifts. One that keeps on giving is “Last Christmas,” the 1984 holiday classic by Wham!, Michael's pop duo with Andrew Ridgeley. “Last Christmas” is such a uniquely beloved song that it inspired a 2019 film of the same name. That’s just one interesting part of the “Last Christmas” story. Read on for 10 fascinating facts about this seasonal synth-pop favorite.

1. George Michael wrote "Last Christmas" in his childhood bedroom.

“Last Christmas” was born one day in 1984 when George Michael and Wham! bandmate Andrew Ridgeley were visiting Michael’s parents. While they were sitting around watching TV, Michael suddenly dashed upstairs to his childhood bedroom and composed the modern Xmas classic in about an hour. “George had performed musical alchemy, distilling the essence of Christmas into music,” Ridgeley said. “Adding a lyric which told the tale of betrayed love was a masterstroke and, as he did so often, he touched hearts."

2. “Last Christmas” isn’t really a Christmas song.

There’s nothing in “Last Christmas” about Santa, reindeer, trees, snow, or anything we typically associate with the holiday. Rather, the song is about a failed romance that just happens to have begun on December 25, when Michael gave someone his heart, and ended on December 26, when this ungrateful person “gave it away.”

3. George Michael wrote and produced the song—but that’s not all.

Singers George Michael (left) and Andrew Ridgeley, of the band 'Wham!', performing on stage, July 1986
Dave Hogan/Getty Images

By the time Wham! recorded “Last Christmas” in August (yes, August) 1984, Michael had taken full control of the group. In addition to writing and producing the song, Michael insisted on playing the Roland Juno-60 synth in the studio. “George wasn’t a musician,” engineer Chris Porter said. “It was a laborious process, because he was literally playing the keyboards with two or three fingers.” Michael even jangled those sweet sleigh bells himself.

4. “Last Christmas” didn’t reach #1 on the UK charts.

As the movie Love Actually reminds us, scoring a Christmas #1 in the UK is a really big deal. Unfortunately, “Last Christmas” didn’t give Wham! that honor. It stalled at #2, and to this day it has the distinction of being the highest-selling UK single of all time to not reach #1.

5. George Michael sang on the song that kept “Last Christmas” at #2.

“Last Christmas” was bested on the UK charts by Band Aid’s “Do They Know It’s Christmas,” an all-star charity single benefiting Ethiopian famine relief. Michael sang on “Do They Know It’s Christmas,” and was so committed to the cause that he donated his profits from “Last Christmas” to helping the African nation.

6. George Michael was sued for plagiarism over “Last Christmas.”

In the mid-1980s, the publishing company Dick James Music sued George Michael on behalf of the writers of “Can’t Smile Without You,” a schmaltzy love song recorded by The Carpenters and Barry Manilow, among others. According to Chris Porter, the recording engineer on “Last Christmas,” the suit was dismissed after a musicologist presented 60-plus songs that have a similar chord progression and melody.

7. "Last Christmas" has been covered by a lot of other artists.

Andrew Ridgeley (right) and George Michael (1963-2016) of Wham! performing on stage together in Sydney, Australia during the pop duo's 1985 world tour, January 1985.
Michael Putland/Getty Images

Jimmy Eat World, Hilary Duff, Good Charlotte, Ariana Grande, Carly Rae Jepsen, Gwen Stefani, and Taylor Swift are just a few of the artists who’ve covered “Last Christmas” over the years. The strangest rendition may be the 2006 dance version by the Swedish CGI character Crazy Frog, which reached #16 on the UK charts.

8. Some people make a concerted effort to avoid hearing “Last Christmas.”

While millions of people delight in hearing “Last Christmas” every year, an internet game called Whamageddon encourages players to avoid the song from December 1 to 24. The rules are simple: Once you hear the original Wham! version of “Last Christmas” (remixes and covers don’t count), you’re out. You then admit defeat on social media with the hashtag #Whamageddon and wait for your friends to suffer the same fate. Note: The rules prohibit you from “deliberately sending your friends to Whamhalla.”

9. “Last Christmas” finally charted in America following George Michael’s death in 2016.

Back in 1984, “Last Christmas” wasn’t released as a commercial single in the United States, and therefore it wasn’t eligible for the Billboard Hot 100 chart. However, Billboard changed its rules in 1998, and in the wake of George Michael’s unexpected death on Christmas Day 2016, the song finally made its Hot 100 debut. In December 2018, it reentered the charts and peaked at #25.

10. George Michael was involved in the Last Christmas movie.

November 2019 saw the release of Paul Feig's Last Christmas, a romantic comedy inspired by the song starring Game of Thrones's Emilia Clarke. Producer David Livingstone came up with the idea while George Michael was still alive, and when he pitched the pop star on the project, he was given the greenlight—with one condition: Michael stipulated that actress and author Emma Thompson write the movie. Thompson co-authored the story and the screenplay, and she even wound up playing a supporting role.

The Origins of 12 Christmas Traditions

Tom Merton/iStock via Getty Images
Tom Merton/iStock via Getty Images

From expecting Santa to fill our footwear with gifts to eating cake that looks like tree bark, the holidays are filled with traditions—some of which are downright odd when you stop and think about them. Where did they come from? Wonder no more. Here are the origins of 12 Christmas traditions.

1. Hanging Stockings

While there’s no official record of why we hang socks for Santa, one of the most plausible explanations is that it's a variation on the old tradition of leaving out shoes with hay inside them on December 5, the eve of St. Nicholas’s feast day. Lucky children would discover that the hay they left for St. Nick’s donkey had been replaced with treats or coins when they woke up the next morning. Another story says that St. Nicholas learned of a father who was unable to pay for his three daughters' dowries, so St. Nick dropped gold balls down a chimney, which landed in stockings hung by the fire to dry. But this appears to be a modern telling—traditional versions of the story generally have the gold land at the father's feet after being thrown through a window.

Regardless of what started the tradition, people seem to have realized the need to use a decorative stocking in place of an actual sock pretty early on. In 1883, The New York Times wrote:

"In the days of the unobtrusive white stocking, no one could pretend that the stocking itself was a graceful or attractive object when hanging limp and empty from the foot of the bedstead. Now, however, since the adoption of decorated stockings ... even the empty stocking may be a thing of beauty, and its owner can display it with confidence both at the Christmas season and on purely secular occasions."

2. Caroling

Though it may seem like a centuries-old tradition, showing up at people’s houses to serenade them with seasonal tunes only dates back to the 19th century. Before that, neighbors did visit each other to impart wishes of good luck and good cheer, but not necessarily in song. Christmas carols themselves go back hundreds of years, minus the door-to-door part. The mashup of the two ideas didn’t come together until Victorian England, when caroling was part of every holiday—even May Day festivals. As Christmas became more commercialized, caroling for the occasion became more popular.

3. Using Evergreens as Christmas Trees

Rows of Christmas trees at tree farm on cold winter morning
arlutz73/iStock via Getty Images

Before Christianity was even conceived of, people used evergreen boughs to decorate their homes during the winter; the greenery reminded them that plants would return in abundance soon. As Christianity became more popular in Europe, and Germany in particular, the tradition was absorbed into it. Christians decorated evergreen trees with apples to represent the Garden of Eden, calling them "Paradise Trees" around the time of Adam and Eve's name day—December 24. Gradually, the tradition was subsumed into Christmas celebrations.

The tradition spread as immigrants did, but the practice really took off when word got around that England’s Queen Victoria decorated a Christmas tree as a nod to her German husband’s heritage (German members of the British royal family had previously had Christmas trees, but they never caught on with the wider public). Her influence was felt worldwide, and by 1900, one in five American families had a Christmas tree. Today, 25 to 30 million real Christmas trees are sold in the U.S. every year.

4. The Colors Red and Green

As with many other old Christmas traditions, there’s no hard-and-fast event that deemed red and green the Official Colors of Christmas™. But there are theories—the green may have derived from the evergreen tradition that dates back to before Christianity, and the red may be from holly berries. While they’re winter-hardy, just like evergreens, they also have a religious implication: The red berries have been associated with the blood of Christ.

5. Ugly Christmas Sweaters

To celebrate this joyous season, many people gleefully don hideous knitwear adorned with ribbons, sequins, bows, and lights. In the past, the trend was embraced solely by grandmas, teachers, and fashion-challenged parents, but in the last decade or so, the ugly sweater has gone mainstream. We may have Canada to blame for that: According to the Ugly Christmas Sweater Party Book, the ugly sweater party trend can be traced to a 2001 gathering in Vancouver.

6. Leaving Milk and Cookies for Santa

Closeup image of wish list and treats for Santa Claus on table next to burning fireplace
Artfoliophoto/iStock via Getty Images

When we plunk a few Oreos or chocolate chip cookies on a plate for St. Nick, accompanied by a cold glass of milk, we’re actually participating in a tradition that some scholars date back to ancient Norse mythology. According to legend, Odin had an eight-legged horse named Sleipnir. Kids would leave treats for Sleipnir, hoping that Odin would favor them with gifts in return. The practice became popular again in the U.S. during the Great Depression, when parents tried to impress upon kids the importance of being grateful for anything they were lucky enough to receive for Christmas.

7. The A Christmas Story Marathon on TBS

If one of the highlights of your holiday is tuning in for 24 hours of watching Ralphie Parker nearly shoot his eye out, you’re not alone—over the course of the day, more than 50 million viewers flip to TBS. The marathon first aired on TNT in 1997, then switched to sister station TBS in 2004. This Christmas marks the 20th year for the annual movie marathon.

8. Yule Logs

Chocolate yule log cake with red currant on wooden background
etorres69/iStock via Getty Images

Throwing a yule log on the fire is another tradition that is said to predate Christianity. As part of winter solstice celebrations, Gaels and Celts burned logs decorated with holly, ivy, and pinecones to cleanse themselves of the past year and welcome the next one. They also believed the ashes would help protect against lightning strikes and evil spirits. The practice was scaled down over time, and eventually, it morphed into a more delicious tradition—cake! Parisian bakers really popularized the practice of creating yule log-shaped desserts during the 19th century, with various bakeries competing to see who could come up with the most elaborately decorated yule log.

If you prefer a wood yule log to one covered in frosting, but find yourself sans fireplace, you can always tune in to Yule Log TV.

9. Advent Calendars

Technically, Advent, a religious event that has been celebrated since the 4th century, is a four-week period that starts on the Sunday closest to the November 30 feast day of St. Andrew the Apostle. Traditionally, it marked the period to prepare for Christmas as well as the Second Coming. These days, it’s mostly used as a countdown to Christmas for the religious and the non-religious alike.

The modern commercialized advent calendar, which marks the passage of December days with little doors containing candy or small gifts, are believed to have been introduced by Gerhard Lang in the early 1900s. He was inspired by a calendar that his mother made for him when he was a child that featured 24 colored pictures attached to a piece of cardboard. Today, advent calendars contain everything from candy to LEGOs.

10. Eggnog

Eggnog in two glass cups
GreenArtPhotography/iStock via Getty Images

It’s hard to imagine why anyone would be inspired to chug a raw egg-based drink, but historians agree that 'nog was probably inspired by a medieval drink called posset, a milky drink made with eggs, milk, and sometimes figs or sherry. These were all pricey ingredients, so the wealthy often used it for toasting.

Eggnog became a holiday drink when colonists brought it over from England, but they found a way to make it on the cheap, nixing the figs and substituting rum for sherry. And how about that weird "nog" name? No one knows for sure, but historians theorize that nog was short for noggin, which was slang for a wooden cup, or a play on the Norfolk variety of beer also called nog (which itself may be named after the cup).

11. Mistletoe

Mistletoe has been associated with fertility and vitality since ancient times, when Celtic Druids saw it as such because it blossomed even during the most frigid winters; the association stuck over the centuries.

It’s easy to see how fertility and kissing can be linked, but no one is quite sure how smooching under the shrub (actually, it’s a parasitic plant) became a common Christmas pastime. We do know the tradition was popular with English servants in the 18th century, then quickly spread to those they served. The archaic custom once allowed men to steal a kiss from any woman standing beneath; if she refused, they were doomed with bad luck.

12. Christmas Cards

Exchanging holiday greetings via mail is a surprisingly recent tradition, with the first formal card hitting shelves in 1843. Designed by an Englishman named J.C. Horsley, the cardboard greeting showed a happy group of people participating in a toast, along with the printed sentiment, "A Merry Christmas and a Happy New Year to you.” A thousand of them were printed that first year, and because it cost just a penny to mail a holiday hello to friends and family (the card itself was a shilling, or 12 times as much), the cards sold like hotcakes and a new custom was born. Today, Americans send around 2 billion cards every year.

SECTIONS

arrow
LIVE SMARTER