Bad Kissingen is a spa town. According to the town’s website, Bavarian King Ludwig II bestowed the “Bad” part of its name on it in 1883, but not because he didn’t enjoy his stay—“bad” means “bath” or “spa” in German. Just south of the Rhön Mountains in Germany, it’s quaintly charming in the way of small European towns (it has a population of about 20,000), particularly those reliant on tourists.
Apparently there’s a bit of a competition among European spa towns—“medical tourism” brings people who want special, specific treatments, or the cheapest possible version of a treatment. So Dr. Thomas Kantermann, of the University of Groningen in the Netherlands, tells me. A friend of his, Michael Wieden, is the official business developer of Bad Kissingen.
“He joined with me to think—if we want to pimp this town, if we want to make it more sexy and attractive, how can we do it?” Kantermann says.
Wieden sought Kantermann out for his particular expertise—Kantermann is a chronobiologist, meaning he studies the differences in people’s circadian rhythms and sleep patterns. A person’s preferred sleep pattern is his or her “chronotype.” This is what we’re talking about when we say someone is a morning person or a night owl. Research has shown that living outside your chronotype, which most of us do—waking ourselves up early with an alarm clock for school or work, or staying out too late at the bars—can lead to all kinds of problems other than just being tired: poor memory, depression, obesity, even a greater risk for some kinds of cancer.
Sleep is mysterious, and we don’t totally understand why we need it—just that we do, and bad things happen if we don’t get enough of it. On average, we spend around 30 percent of our lives asleep, but as a review of the literature on circadian rhythms from 2005 notes, “The introduction of artificial lighting and the restructuring of working hours has progressively detached our species from the 24-hour cycle of light and dark. … At best we tolerate the fact that we need to sleep, and at worst we think of sleep as an illness that needs a cure.”
Not so in Bad Kissingen.
Though the initiative’s sexiness is perhaps debatable, in an effort to stand out from the pack and improve the lives of its citizens and visitors, Bad Kissingen has committed itself to finding ways to implement chronobiology into the fabric of the town’s society.
“The history of Bad Kissingen has [always] been linked to curation and health,” Wieden says. “We have 17 hospitals, sanatoriums and rehabs. We have about 250,000 guests per year. Hence, tourism and health treatment are closely linked in Bad Kissingen. Therefore, to me, Bad Kissingen is the best place in the world to start a ‘whole city project’ like this.”
Russell Foster, a professor of neuroscience at Oxford University, studies chronobiology but is not involved in the Bad Kissingen project. “Changing behavior in any area is really difficult,” he says, and notes a classic study in which researchers observed a population of monkeys slowly learning to wash their food in the ocean to get the sand off. “The ones that were slowest to adopt [the washing behavior] were at the top of the social hierarchy.” Similarly, if those in charge of scheduling our lives—school boards, bosses, etc.—aren’t amenable to change, it’s next to impossible to truly sleep like yourself.
But there Bad Kissingen has the advantage of buy-in from the top. Kantermann is the project’s scientific manager, and in July 2013, he, Wieden, Bad Kissingen’s mayor and town council, and other researchers from the University of Groningen and the Ludwig Maximilian University of Munich signed a letter of intent. In that letter, they pledged to promote chronobiology research in the town, to “gather results that are directly applicable to living, education, work, well-being, health, mobility, rehabilitation, and sleep.” It goes on to claim that “the city of Bad Kissingen will be the first in the world realizing scientific field studies in a wider context.” Those involved often refer to Bad Kissingen as “ChronoCity.”
Though it was first conceived more than a year ago, the project is still in its infancy—it takes time and careful planning to do anything on this scale. Plus, Kantermann says, they need more money.
The goal is to get all of the town’s citizens’ chronotypes in an online database. Right now, individuals have to go to this website and input their own data; the hope is that one day schools and hospitals will take down this information as regularly as someone’s height or weight, making it much easier to determine and work with the town’s needs.
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The roots of the field of chronobiology are actually leaves. The concept was born in France in 1729, when astronomer Jean-Jacques d'Ortous de Mairan noticed that the leaves of his heliotrope plant closed and opened at the same time every day. So he enclosed the plant in a dark space, and found that the leaves continued their punctual dance, sun or no sun.
In this way, humans are not unlike plants, as German biologist Jürgen Aschoff discovered in the 1950’s. He built an underground bunker, where human subjects would stay, cut off from light, sound, and the Earth’s vibrations, so they would have no way to tell what time of day it was. (He went in the bunker himself, first, before experimenting on others.) Most people still kept pretty close to a 24-hour day, though some went for 48 hours, and slept for 16. This confirmed Aschoff’s earlier research (which he also did on himself) that found that that humans lose body heat in regular, 24-hour patterns. Along with U.S. biologist Colin Pittendrigh, Aschoff is considered a co-founder of the field of chronobiology. Fitting, then, that a German town should be the first to try to take chronobiology mainstream.
“It’s a quite young field actually, especially the human part,” Kantermann says. “It’s only 50 to 60 years old. Now we have more sophisticated sleep labs where we do it, though, [instead of] a bunker.”
Kantermann explains that the way we measure someone’s chronotype now uses a metric called “mid-sleep.” This is the halfway point between when you fall asleep, and when you wake up. So if you go to bed at midnight, and get your recommended eight hours, waking up at 8 a.m., your mid-sleep would be 4 a.m.
Teenagers, it is widely known, have some of the latest chronotypes around. Their mid-sleep is often as late as 6 or 7 a.m., according to Kantermann. “We have school starting at that time in Germany, at half past seven, or 8 o’clock, which means these students are sitting [in class] in the middle of their biological night,” he says.