Waking up tired in the morning? You’re not the only one. In fact, thanks to data collected from a free smartphone app, researchers at the University of Michigan have discovered a national epidemic of sleep deprivation. In the U.S., one out of every three people aren’t hitting the recommended goal of seven hours of shut-eye, which could contribute to a number of health problems including obesity, diabetes, high blood pressure, heart disease, stroke, and stress.
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The study made use of a free smartphone app called Entrain, which helps stymie the effects of jet lag by helping travelers adjust to new time zones. Users log their typical hours of sleep and exposure to light, and some users submitted their information anonymously to the University, allowing researchers to “gather robust sleep data from thousands of people in 100 nations.”
Based on this information, the Michigan-based team analyzed the effects of age, gender, amount of light, and home country on the amount of time individuals spend asleep.
Most notably, scientists concluded that “cultural pressures can override natural circadian rhythms,” which means that society, more than your body, actually determines when you go to bed and when you wake up.
“Across the board, it appears that society governs bedtime and one’s internal clock governs wake time, and a later bedtime is linked to a loss of sleep,” said Daniel Forger, a professor at the University of Michigan. “At the same time, we found a strong wake-time effect from users’ biological clocks — not just their alarm clocks. These findings help to quantify the tug-of-war between solar and social timekeeping.”
Curiously enough, social norms were linked most closely to when individuals went to bed, not necessarily when they woke up. And ultimately, the time at which you finally lay your head down determines how much sleep you receive. As such, people from countries like Japan and Brazil get less sleep because they go to bed later than, say, those from the Netherlands and Belgium, where the national bedtime appears to be a bit earlier.
So if you’re looking to get some more shuteye, you may want to consider moving to a country with different social norms.