A new survey published in the journal Sleep finds that, on average, Americans are slowly but surely getting more shut-eye, even if it’s just a few minutes each week. The findings show that, overall, people seem to be turning in a little earlier and spending less time watching TV or reading just before bed.
The research, based on the American Time Use Survey (ATUS), found that daily sleep duration increased by 1.4 minutes on weekdays and 0.8 minutes on weekends each year.
At first glance, this may not seem like much progress. However, over the 14-year period it translates to 17.3 minutes more sleep each night, or 4.4 full days more sleep each year. Overall, these numbers amount to an extra 7.5 hours of sleep each year over the 14-year period. The survey involved 181,335 respondents aged 15 and older between 2003 and 2016.
The study, conducted by researchers at the Perelman School of Medicine at the University of Pennsylvania, is the first to show that sleep duration has increased among several segments of the United States population (students 15 and older, people who are employed, and retirees) during this period.
The increase in sleep duration was mostly explained by people going to bed earlier at night, and to a lesser degree by getting up later in the morning.
In addition to sleep, the ATUS asks participants about their daily activities, and thus allows Penn researchers to investigate behaviors that could be responsible for the increase in sleep duration. For example, over the 14-year period, fewer respondents chose to read or watch TV right before bed in the evening, two prominent activities that compete with sleep for time.
“This shows an increased willingness in parts of the population to give up pre-bed leisure activities to obtain more sleep,” said the study’s lead author, Mathias Basner, M.D., Ph.D., an associate professor of Sleep and Chronobiology in Psychiatry.
“Also, the data suggest that increasing opportunities to work, learn, bank, shop, and perform administrative tasks online and from home freed up extra time, and some of it was likely used to get more sleep.”
The researchers found no notable sleep time trend regarding unemployed respondents or those not in the labor force, thus bringing more attention to the difficulty of work/family balance and the finding that sometimes people sacrifice sleep to make the other two work.
In previous research, the Penn team found that work was the number one waking activity competing with sleep for time. However, changes in time spent working were not found to play a substantial role in the increasing sleep time trend in this study.
The findings also show that the number of Google searches on the topic “sleep” has more than doubled and scientific publications on “short sleep” and its consequences has grown more than 10 fold from 2003 to 2016, and was highly correlated with the increase in sleep duration.
Although this does not prove causality, the researchers say this offers some hope that the increasing awareness of insufficient sleep and its consequences as well as campaigns to encourage healthy sleep — such as the 2013 National Healthy Sleep Awareness Project — may be helping.
The dangers of sleep deprivation are well-documented. Earlier research shows that cognitive performance and vigilant attention decline quickly after being awake longer than 16 hours or if sleep is chronically curtailed, which increases the risk for errors and accidents.
In addition, studies have linked chronic short sleep to obesity, hypertension, diabetes, cardiovascular disease, and declines in cognitive function.
In 2015, the American Academy of Sleep Medicine and Sleep Research Society published a consensus statement that adults should sleep seven or more hours per night on a regular basis to promote optimal health.
Source: Penn Medicine