Is Daylight Saving Time to Blame for Seasonal Depression?

iStock
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.

Alcohol-Producing Gut Bacteria May Harm Livers—Even if You Don't Drink

itakdalee/iStock via Getty Images
itakdalee/iStock via Getty Images

Teetotalers might think their liver is safe from the damaging effects of alcohol consumption, but new research is hinting that even non-drinkers and light drinkers might have cause for concern. It turns out a type of gut bacteria is capable of producing alcohol—and enough of it to potentially cause some pretty serious health consequences, including liver disease.

A study led by Jing Yuan at the Capital Institute of Pediatrics in Beijing, China and published in the journal Cell Metabolism offers details. After evaluating a patient with auto-brewery syndrome (ABS), a rare condition brought on by consumption and fermentation of sugary foods that leaves a person with high blood alcohol levels, researchers made an intriguing discovery. Rather than finding fermenting yeast that may have led to the condition, the patient’s stool contained Klebsiella pneumonia, a common gut bacteria capable of producing alcohol. In this subject, K. pneumonia was producing significantly more alcohol than in healthy patients.

The patient also had nonalcoholic fatty liver disease (NAFLD), characterized by fatty deposits in the liver. While many cases of NAFLD are relatively benign, too much fat can become toxic. Examining 43 other subjects with NAFLD, scientists found that that K. pneumonia was both present and potent, pumping out more alcohol than normal in 60 percent of participants with NAFLD. In the control group, a surplus was found in only 6.25 percent.

To further observe a correlation, scientists fed the bacteria to healthy, germ-free mice, who began to see an increase in fat in their livers after only one month. While not conclusive proof that the bacteria prompts NAFLD, it will likely trigger additional research in humans.

It’s not yet known how K. pneumonia acts in concert with the bacterial profile of the gut or what might make someone carrying stronger strains of the bacteria. Luckily, K. pneumonia can be treated with antibiotics. That’s good news for people who might never touch a drink and still find themselves with a damaged liver.

[h/t Live Science]

Visit Any National Park for Free on September 28—or Volunteer to Help Maintain Them

Yosemite National Park
Yosemite National Park
Nick Hanauer/iStock via Getty Images

By the end of September—which always seems especially busy, even if you’re not a student anymore—you might be ready for a small break from the hustle and bustle. On Saturday, September 28, you can bask in the tranquility of any national park for free, as part of National Public Lands Day.

According to the National Park Service, the holiday has been held on the fourth Saturday of every September since 1994, and it’s also the nation’s largest single-day volunteer effort. It’s up to you whether you’d like to partake in the service side or simply go for a stroll, but there is an added incentive to volunteer: You’ll get a one-day park pass that you can use for free park entry on a different day. Opportunities for volunteering include trail restoration, invasive plant removal, park cleanups, and more; you can see the details and filter by park, state, and/or type of event here.

If you’re not sure how you should celebrate National Public Lands Day, the National Park Service has created a handy flowchart to help you choose the best course of action for you—which might be as simple as sharing your favorite outdoor activity on social media with the hashtag #NPLD.

National public lands day celebration flowchart
National Park Service

There are more than 400 areas run by the National Park Service across the U.S., and many of them aren’t parks in the traditional sense of the word; the Statue of Liberty, Alcatraz Island, and countless other monuments and historical sites are also run by the NPS. Wondering if there might be one closer than you thought? Explore parks in your area on this interactive map.

For those of you who can’t take advantage of the free admission on September 28, the National Park Service will also waive all entrance fees for Veteran’s Day on November 11.

And, if you’re wishing a free-admission day existed for museums, you’re in luck—more than 1500 museums will be free to visit on Museum Day, which happens to be this Saturday.

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