#137: ⏰ When Society’s Schedule Clashes With Your Biological Clock
You have….social jet lag.
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💬 In this note:
⏰ When Society’s Schedule Clashes With Your Biological Clock
📚 Abroad in Japan
⚡️ Strong Grandma
#137: ⏰ When Society’s Schedule Clashes With Your Biological Clock
I've been thinking a lot about time lately.
Not in the abstract, philosophical sense, but in the very real, wake-up-at-6-AM-when-your-body-wants-to-sleep-until-9 sense.
Maybe you know the feeling.
Sunday night rolls around and you dread Monday morning not just because it's Monday, but because your entire system feels like it's fighting against the clock.
Turns out, there's a name for this phenomenon, and it's affecting millions of us every single day.
It’s called Social Jet Lag.
Social jet lag describes the misalignment between your body's natural circadian rhythm and the schedule society demands of you.
It's the phenomenon that occurs when your internal clock says "sleep" but your alarm clock says "work."
The term was coined by Professor Till Roenneberg at the University of Munich in the early 2000s, and it perfectly captures what millions of people experience daily.
If you naturally fall asleep at midnight and wake up at 8 AM on weekends, but you're forced to wake up at 6 AM for work, you're essentially living with a two-hour time difference every weekday.
Your body experiences this as constantly traveling between time zones, without ever actually traveling.
The Science Behind Your Internal Clock
Your circadian rhythm controls your biological processes.
It controls when you feel alert, when you get hungry, when your body temperature rises and falls, and crucially, when you feel sleepy.
This internal clock is primarily driven by your chronotype, if you are a morning bird or a night owl.
About 25% of people are naturally early risers, 25% are true night owls, and the remaining 50% fall somewhere in between.
Here's the problem: our society is built for the morning birds.
Standard work schedules, school start times, and social expectations all favor those whose natural rhythm aligns with early rising.
But for the significant portion of the population who are naturally night owls, this creates a chronic mismatch between biology and obligation.
The Weekly Cycle of Misalignment
The pattern is predictable and brutal.
Monday through Friday, night owls drag themselves out of bed earlier than their bodies want, accumulating what researchers call "sleep debt."
They rely on caffeine, willpower, and sometimes pure stubbornness to function during their biological low periods.
Then comes the weekend.
Finally free from social constraints, they revert to their natural sleep schedule, staying up later and sleeping in longer.
This feels restorative, but it sets them up for an even harder Monday morning.
It's like being caught in a weekly cycle of jet lag, constantly shifting between your natural time zone and society's imposed schedule.
The Hidden Health Costs
Social jet lag isn't just about feeling groggy on Monday mornings. Research has linked chronic circadian misalignment to serious health consequences.
Studies show that people with significant social jet lag have higher rates of obesity, diabetes, cardiovascular disease, and depression.
They're more likely to smoke, drink alcohol, and consume caffeine.
Their immune systems may be compromised, and their cognitive performance can suffer.
When your biological processes are constantly fighting against imposed schedules, your entire system becomes stressed and dysregulated.
Shift workers are a well-researched group who show the effects of extreme social jet lag. In fact, shift worke leads to partial sleep deprivation, which leads to higher rates of metabolic disorders and accelerated aging at the cellular level.
Beyond Individual Impact
The effects of social jet lag extend beyond personal health.
Students whose chronotypes don't match school start times show decreased academic performance.
Workers experience reduced productivity and increased accident rates when forced to work against their natural rhythms.
Some countries and organizations are beginning to recognize this. Germany has experimented with later school start times for teenagers, whose circadian rhythms naturally shift later during adolescence.
Students slept better. They felt less exhausted dragging themselves through the day. Their minds could actually focus during class instead of fighting to stay awake. And, they could concentrate better when studying at home too.
Some companies now offer flexible work schedules that allow employees to align their work hours with their natural rhythms.
Think flexible work is some post-COVID invention? Think again.
Companies have been experimenting with flexibility for decades.
Way back in 1967, a Munich aerospace company called Messerchmitt-Bölkow-Blohm had a problem. Employees were constantly late or calling in sick. So they brought in sociologist Kristel Kammerer to figure it out.
Her solution was to let people choose when to start and finish work. Give them flexible lunch breaks. Let them bank extra hours.
And the employees loved it.
Companies that adopt flexible working hours typically see several benefits.
They see greater productivity from their employees, ability to attract talent they’d never find otherwise, increases in job satisfaction, improved employee retention and lower stress from employees that don’t have to commute in peak hours.
Finding Your Natural Rhythm
The first step in addressing social jet lag is understanding your own chronotype.
Pay attention to when you naturally feel sleepy and alert during periods when you don't have to follow a strict schedule, like vacations or weekends.
If you consistently want to sleep at midnight and wake at 8 AM when left to your own devices, but you're forced to wake at 6 AM for work, you're experiencing two hours of social jet lag.
Another big indicator that you experience social jet lag is if you are on vacation and you sleep for several days for 10+ hours.
While we can't always change our schedules, we can minimize the impact.
Gradual schedule shifts, strategic light exposure, and understanding your natural energy patterns can help reduce the misalignment.
Society vs. Biology
Social jet lag reveals something important about how we structure society.
We've created a one-size-fits-all approach to time that simply doesn't match human biological diversity.
Just as we're beginning to understand the importance of personalized medicine and nutrition, perhaps it's time to consider personalized schedules.
The technology exists to accommodate different chronotypes in many workplaces and schools.
The question is whether we're willing to challenge the assumption that early rising is inherently virtuous and acknowledge that optimal performance and health might require honoring our natural biological rhythms.
Your body has been keeping time for millions of years of evolution. Maybe it's worth listening to what it's trying to tell you.
📚 Book of the Week
Abroad in Japan by Chris Broad
Rating: ★★★★☆
This isn't your typical travel memoir.
Chris Broad, a British teacher who moved to rural Japan, offers a refreshingly honest and hilarious look at the culture shock, language barriers, and unexpected adventures of living as a foreigner in Japan.
What makes this book particularly engaging is Broad's ability to find humor in uncomfortable situations while maintaining genuine respect for Japanese culture.
He writes about everything from the complexities of Japanese toilets to the isolation of being unable to communicate effectively, all with a self-deprecating wit that makes you feel like you're sharing a drink with a friend.
The book perfectly captures the disorientation that comes with living in a completely different time zone - both literally and culturally.
If you've ever wondered what it's really like to completely uproot your life, this book delivers both laughs and genuine insights about adaptation, resilience, and finding your place in an unfamiliar world.
This was a reader recommendation from Harry! Thanks Harry!
⚡️ Check This Out
Catherine Keuhn is 95 years old, deadlifts, and she’s a world-record powerlifter.
She says,
“It’s been easy for me, because no one my age was doing it.”
The documentary Strong Grandma by Cecilia Brown and Winslow Crane-Murdoch, follows Kuehn as she prepares for what may be her final competition.
She picked up the sport in her 80s. She shows that age is just a number, and the importance of strength training into our later years.
Also, Catherine shows is that it’s never too late to become a badass.
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