May 8, 2016
Scientists Warn Of 'Global Sleep Crisis'

A new study using data collected via a smartphone app worldwide reveals that modern-day social pressures are forcing people to cut back on sleep, contributing to a "global sleep crisis," scientists say.

Scientists from the University of Michigan tracked the sleep patterns of people from all around the world using the free, no-ad app, Entrain. The app was originally designed and released in 2014 to help fight jetlag by mathematically generating lighting schedule recommendations, enabling users to adjust to new time zones as quickly as possible. But the research team asked users of the app aged 15 and older to share anonymous sleep, waking time, and lighting data. In addition to their sleeping habits, users could share their age, gender, time zone, and country of origin.

The study, published in the journal, Science Advances, analyzed the data from more than 6,000 people collected from 100 different countries. What they've found, unfortunately, is not good.

Cultural and social pressures to stay up at night for work or fun is keeping more and more people up each night. People who tend to not get a good night's rest do so because of the time they go to bed, as societal pressures override our natural circadian rhythms. Those who under-slept also experienced reduced cognitive abilities throughout the day. Lack of sleep is widespread enough in the human population that it constitutes a "global crisis" right now, according to scientists.

The average amount of sleep varies from country to country. People in Japan and Singapore had an average of seven hours and 24 minutes of sleep, while the people in the Netherlands got eight hours and 12 minutes on average, giving the Dutch nearly an hour more in bed every night. While this may not sound significant, even a difference of 30 minutes can have an impact on a person's health and how they function for the rest of the day.

Canadians tended to wake up after 7 a.m., a sleep pattern more similar to people in the U.K. than in the U.S. Canadians also had a total average sleep time of more than 7.9 hours, while people in the U.K. averaged just under eight hours. All in all, it was a country's average bedtime that had the biggest impact on total sleep time: the later a country's people stayed up at night, the less sleep they got. What time they woke up seemed to have a negligible effect on total sleep time.

"The effects of society on sleep remain largely unquantified," the study said. "We find that social pressures weaken and/or conceal biological drives in the evening, leading individuals to delay their bedtime and shorten their sleep."

On average, women got about 30 more minutes of sleep per night than men, particularly between the ages of 30 and 60. People with more time in natural light tended to go to bed earlier. The researchers found that age is the main factor in determining the quality of sleep someone gets, and that middle-aged men were the most vulnerable to sleep deprivation, according to CBC News.

"It is middle-aged men that seem to be getting a remarkably little amount of sleep, and we think that is very significant," the study's lead author, math Professor Daniel Forger of the University of Michigan in Ann Arbor, said in an interview. "They are behind the wheel driving trucks, driving airplanes and when they do it with so little sleep, that can pose risks to themselves and also to society."

CBC News summed up some of the study's main findings.

"Middle-aged men often get less than the recommended seven to eight hours of shut-eye. Women schedule about 30 more minutes of sleep on average by going to bed earlier and waking up later. Age is the main driver of sleep timing. Sleep schedules were more similar among those 55 and older than those younger than 30. As people get closer to retirement, the researchers suspect our bodies will only let us sleep at certain times of the day."
The team of scientists believes that impaired sleep constitutes an immediate and pressing need to human health. Studies show that not getting enough deep sleep can lead to an increased risk of obesity, Type 2 diabetes, heart problems, and other health problems.

[Photo by Sean Gallup/Getty Images]