Is Daylight Saving Time to Blame for Seasonal Depression?

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iStock

The precise root cause of seasonal depression has eluded scientists for years. Now researchers think they’ve found the answer: daylight saving time. They published their report in the journal Epidemiology.

Seasonal depression or seasonal affective disorder (SAD) affects around 1.6 billion people across the globe. Its symptoms mirror those of generalized depression; what differentiates SAD is the timing of its onset, which coincides with winter’s shorter days and long, dark nights.

We know that sunlight, or the absence of it, has a powerful effect on our bodies. But scientists have yet to find a definitive physiological link between darkness and SAD, a fact that makes some wonder if there aren’t other variables at play.

Previous studies have found a relationship between the shift from daylight saving into standard time and other health problems, but they had not looked specifically at the transition’s effect on depression. To get a better idea, an international team of researchers looked at Danish hospital intake records from 1995 to 2012, including 185,419 diagnoses of depression.

As expected, they saw an increase in hospital admissions for depression as winter descended. But that increase spiked at one particular time: the month immediately following the changing of clocks.

The researchers controlled for variables like day length and weather, which they say confirms that the 8 percent rise in depression diagnoses was not a coincidence.

And while their study focused on people with severe depression, the authors say the time shift likely affects “the entire spectrum of severity."

Though the study did not identify the mechanism responsible for time change–related depression, the researchers believe it may have something to do with the way daylight saving manipulates our hours of light and dark. Danish daylight saving protocol steals an hour of daylight from the afternoon and moves it to the early morning—a time, the authors say, when most people are indoors anyway.

"We probably benefit less from the daylight in the morning between seven and eight, because many of us are either in the shower, eating breakfast or sitting in a car or bus on the way to work or school. When we get home and have spare time in the afternoon, it is already dark," co-author Søren D. Østergaard of Aarhus University Hospital said in a statement.

Then there are the psychological effects. In changing the clocks, we are forced to acknowledge the arrival of months of darkness, a realization that Østergaard says “is likely to be associated with a negative psychological effect.”

Fortunately, while we still don’t fully understand the causes of SAD, we have found effective treatments. If you find yourself depressed as the year winds down, talk to your doctor and look into a therapeutic light box.

The Unkindest Cut: The Chainsaw Was Invented to Assist With Difficult Childbirths

viafilms/iStock via Getty Images
viafilms/iStock via Getty Images

There’s always a price to be paid for innovation. Usually that amounts to some sleepless nights and lots of trial and error. But sometimes it means attempting to deliver babies with a chainsaw.

This dark chapter in agricultural history comes from Popular Science, which recently detailed how the motorized cutting tool populating Home Depot shelves came to be. In the 18th century, two Scottish surgeons named John Aitken and James Jeffray devised a solution they could employ when faced with difficult childbirths. Rather than use a knife to widen the pelvic area by slicing through cartilage and bone to extricate a stuck baby, the two developed a chainsaw to make cutting easier.

While this sounds ghastly, the doctors were actually trying to lessen the agony endured by women who needed their pelvic bone separated. The knife took a long time, while their device—a modified knife with serrated “teeth” on a chain—could cut through bone and tissue more quickly.

If circumstances warranted it, the doctor would grab the saw, which had a handle on both ends, and wrap the chain around the pelvic bone, pulling each handle so the chain would cut into the bone. Later, the device was outfitted with a hand crank. Thanks to this innovation, difficult births could be described as merely agonizing as opposed to extended torture.

The procedure was dubbed a symphysiotomy and remained in use in the medical field as surgeons noticed how efficiently it could work in other circumstances, like amputations. It lasted through much of the 19th century as part of a surgical toolbox until C-sections grew in popularity. In the 20th century, the principle was commandeered for less disturbing purposes like logging, with two-person saws weighing more than 100 pounds each. By the 1950s, those gave way to lighter models.

For all its discomfiting history, at least the chainsaw proved to be useful—which isn't something that can be said for all inventions purporting to aid in childbirth. In 1965, George and Charlotte Blonsky patented a device that acted as a human turntable, spinning so quickly it might induce the patient (or victim) into delivering their baby via centrifugal force.

[h/t Popular Science]

Kane Tanaka, World’s Oldest Living Person, Just Celebrated Her 117th Birthday

Ruletka, iStock via Getty Images
Ruletka, iStock via Getty Images

Less than a year after being named oldest living person in the world, Kane Tanaka has reached a new milestone. As Reuters reports, Tanaka celebrated her 117th birthday on January 2, 2020, extending the Guinness World Record-winning streak she set in March 2019.

Kane—the seventh of eight siblings—was born on January 2, 1903 in Fukuoka, Japan. She married Hideo Tanaka in 1922, and the couple had five children. Today, she is a grandmother to five and a great-grandmother to eight.

Tanaka celebrated her birthday at the Fukuoka nursing home where she resides, surrounded by friends and family. After taking a bite of her birthday cake, she reportedly said, “Tasty, I want some more." On a typical day, Tanaka spends her time studying math, practicing calligraphy, and beating the nursing home staff at board games.

The 117 club is an exclusive group only a handful of women has entered in recent history. In the last few years, Emma Morano of Italy, Violet Mosse Brown of Jamaica, and Nabi Tajima and Chiyo Miyako of Japan all reached age 117 and were each the oldest person alive for a brief period. If Tanaka celebrates another birthday next year, she will be the first person since the 1990s to live to 118.

[h/t Reuters]

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