Tag Archives: jet lag

Many Americans suffer from “social jet lag”, new social media study shows

Social media activity mirrors our own bodily activity — a new analysis based on this data found that many people are experiencing so-called “social jet lag”, particularly during the weekends.

Jet lag is a well-known phenomenon: when we travel to a very different timezone, our body and sleep pattern has a hard time adjusting to the new conditions — but what if you could travel to a different time zone, without actually traveling?

In a new study published in the journal Current Biology, researchers from the University of Chicago analyzed the Twitter activity of more than 246,000 users from 2012 to 2013, looking for daily patterns of usage. Naturally, people tweet during their awake time, so researchers used social media activity as a proxy for when people were awake and when they were sleeping.

However, researchers observed an interesting trend: during weekdays and holidays, people went to bed later. It was as if, for the duration of the free days, people traveled to a different time zone.

“When we look at how social jet lag changes throughout the year, we find that the dominant effect by far is the social calendar,” says Michael Rust of The University of Chicago. “It suggests that humans in modern societies, at least people who used Twitter in 2013-2014, have biological rhythms that are somewhat disconnected from the changing hours of sunlight throughout the year.”

The shift wasn’t uniform. For instance, the West Coast experienced significantly less Twitter social jet lag than central and eastern US. There was also a seasonal variation, as well as a correlation with average commuting schedules. This was not unexpected, but overall, the results surprised researchers — the impact of the “social pressure” is much stronger than expected.

“We started the study expecting it to be a solar or seasonal effect—that your internal clock will shift in the summer and that will lead to decreases in social jet lag,” said Aaron Dinner, Ph.D., professor of chemistry and one of the study’s senior authors. “But in fact, that’s not what we found at all. People get up later on weekdays in the summer because their social constraints are relaxed. Weekend behavior—and presumably a person’s biological clock—does not change much over the year in most counties.”

This is not the first study to address social jet lag. The misalignment of biological and social time has been associated with smoking and drinking alcohol, and has naturally been shown to be linked to bad mood, worse overall performance, and heart disease. The impact that social media has on our social lives is not negligible, but the fact that public, open-access data can paint such a clear picture of social jet lag is remarkable. However, it should be said that in 2013-2014, when the data was gathered, Twitter’s geolocation was turned on by default, which is not the case now. Twitter also significantly changed its focus, switching from what was once a platform about day-to-day communication to an endless barrage of news and quirky tidbits.

Even so, it’s impressive how much you can draw from open data — our data, that is.

“I was impressed that so much could be learned from this purely public data set that was not at all intended to tell you about sleep,” said Michael Rust, Ph.D., associate professor of molecular genetics, cell biology and physics and the study’s other senior author. “In fact, we could rediscover things like the correlation with obesity or levels of social jet lag based on time zone that were found in other studies where people designed surveys to ask about sleep directly.”

Of course, back in 2013, the world was just starting to understand just how much social media can breach our privacy, and hopefully, the age of “geolocation by default” is over — but that doesn’t mean that we can’t reap the benefits of high quality social data — on the contrary, Rust believes that the future looks quite exciting.

“What is most exciting is the possibility of using devices where a user opts in to provide data, like a smartwatch or fitness tracker,” Rust said. “If we were able to get access to the kind of data where you can follow one person over time and see how the rhythms of their behavior are changing, you might be able to give that person quite useful information about their biological clock.”

The study “Geographically resolved rhythms in Twitter use reveal social pressures on daily activity patterns” has been published in Current Biology.


Planet Earth.

Delaying meals can alter the body clock and solve some of that jet lag

Flying in another time zone or working graveyard shifts messes up with our circadian rhythms and ultimately triggers a slew of health problems. Research suggests that one in five people living in Western countries who work at odd hours are putting their lives at risk since their schedule has been linked to obesity, diabetes, heart disease, even cancer. Now, a new study suggests delaying meals can delay metabolic functions governed by the biological clock, too. The work suggests that changing meal times, coupled with light exposure, can help synchronize the ‘clock’ and reduce health problems.

Planet Earth.

Credit: Pixabay.

The notion that our bodies’ biology runs in cycles known as circadian rhythms — also known as sleep/wake cycle or body clock — is becoming more and more established. This complex timekeeping system is controlled by an area of the brain that responds to light, which is why humans are most alert while the sun is shining and are ready to sleep when it’s dark outside.

Humans don’t have a single body clock but a complex network of clocks — as many as there are cells in the body. In mammals, all of these ‘clocks’ are synched with a master clock which beats by the rhythm set in a region of the brain called the suprachiasmatic nuclei (SCN) but also with peripheral clocks found elsewhere, like in various other organs.

It’s the circadian rhythm that ultimately influences sleep-wake cycles, hormone release, body temperature and other important bodily functions. That’s why disrupting this biological clock can come at a hefty cost to our health. Sometimes, though, such situations are inevitable, like in a work setting — what to do?

Previous research has established that there’s a link between nutrition and the circadian rhythm but it’s only recently that this connection has been traced out in broader detail. Researchers at the University of Surrey in the UK recruited ten healthy volunteers who were fed three meals a day at exactly the same times every day for five days. After this initial round, the researchers delayed each meal time by five hours on the following six days. Each daily meal was identical in caloric and macronutrient content and at the end of the six days, the volunteers had to stay awake for 37 hours. They had small, identical snacks every hour for sustenance and dim lighting, in order to measure any change in their circadian rhythms.

These shifts caused a change in the cycle of blood sugar levels.

“A 5-hour delay in meal times causes a 5-hour delay in our internal blood sugar rhythms,” said Jonathan Johnston, one of the authors of the new study published in Current Biology. “We think this is due to changes in clocks in our metabolic tissues, but not the ‘master’ clock in the brain.”

Later, the authors found that the way a certain clock gene released instructions in white fat tissue was delayed after the shift in meal times. Seeing how the ‘master clock’ wasn’t affected, the researchers reckon the delayed meals caused changes in the peripheral clocks without affecting the master clock.

Most jet lag and shift work therapies revolve around controlling light exposure but this sort of intervention seems to work on the master clock only. Changing meals, on the other hand, can help the peripheral clocks come up to speed as well, thus reducing desynchronisation of the body’s clocks.

Keep in mind, though, that this was a small study which needs more validation before we can draw sound conclusions. It does suggest, however, that delaying breakfast for a couple of hours if you flew from London to Moscow can help. Nothing seems to beat a whole week camping under the stars, though.

Re-Timer Glasses

Curing jet lag with timezone adjusting LED glasses

Re-Timer GlassesAlong with technology came a series of new afflictions that plagued mankind. Most of them are psychological, like internet addiction or the ever worrisome jet lag. The latter is a big problem for millions of people regularly traveling in different time zones, causing them to miss hours of sleep, feel extremely tired, not eat well and feel depressed. Australia’s Flinders University sleep researchers recently released on the market an interesting pair of goggles called the Re-Timer that uses LEDs to regulate light flow and reset your internal clock.

Jet lag has a sort of natural correspondent, although nothing of the sorts as extreme, in the form of seasonal shifts of day and night hours. This is something commonly known as winter blues, and many of us suffer from it, especially when the number of daylight hours is low. Staying too much time indoors is also known to cause a similar affect on people. In all, they all point to the same thing – disruption of the body clock through inconsistent light exposure.

Our bodies have used sunlight to regulate our sleeping and waking pattern, which in term governs our mood and well-being, for tens of thousands of years; early ancestors for much more. The researchers’ device concentrates on this exact light mismatch to counter effects like jetlag, by emitting a soft green LED light into your eyes.

“The light from Re-Timer stimulates the part of the brain responsible for regulating the 24-hour body clock,” Professor Leon Lack said.

“Body clocks or circadian rhythms influence the timing of all our sleeping and waking patterns, alertness, performance levels and metabolism.”

Those who wanted to sleep and wake up earlier should wear the device for 50 minutes in the morning, while those who want to sleep and wake later should wear them for 50 minutes before bed to delay the body clock. The glasses can be worn while completing normal daily tasks such as working on the computer or reading.

“Our extensive research studies have shown that green light is one of the most effective wavelengths for advancing or delaying the body clock, and to-date is the only wearable device using green light,” Prof Lack said.

“The glasses have been designed to be user friendly and comfortable to wear so people can go about their normal activities wearing them at work or at home.”

The device is explained in a video featured below. The Re-Timer is commercially available for $258. Scientific research that backs the Re-Timer features can be found here.

via Dvice