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(CNN) Americans are failing In their endless quest for adequate slumber, leading to deficits that can impact health, according to a new study on sleep habits in the United States.
The study, which authors called the the first to separately evaluate sleep duration between workdays and free days, analyzed sleep data on over 9,000 Americans age 20 and older collected by the National Health and Nutrition Examination Survey between 2017 and March 2020.
Almost 30% of respondents had trouble falling or staying asleep and about 27% were very sleepy during the day, according to the study published Tuesday in the journal JAMA Network Open.
The analysis also found over 30% of adults reported an hour of sleep debt -— when you sleep less than your body needs — while nearly 1 in 10 adults had a sleep debt of two hours or more.
Adults over 18 need at least 7 hours of solid sleep at night to be healthy, according to the US Centers of Disease Control and Prevention. Sleep debt, along with irregular sleep duration, has been linked to an increased risk of obesity, heart disease, dementia and mood disorders such as anxiety and depression.
"This is a well done study examining a very large and representative sample," said Dr. Bhanu Prakash Kolla, a sleep medicine specialist in the Center for Sleep Medicine at the Mayo Clinic in Rochester, Minnesota.
"At least a quarter of the population complained of daytime sleepiness and difficulties with sleep," said Kolla, who was not involved in the study.
In addition, nearly half of the adults in the study reported social jet lag -- a bad fit between the sleep timing preferred by a person's inner biological clock and the one dictated by society.
"The timing of your sleep on workdays is the societal and work constraints, but the timing of your sleep on free days is what your body clock really wants you to do," said Dr. Elizabeth Klerman, a professor of neurology in the division of sleep medicine at Harvard Medical School in Boston.
If you have a big difference between the two, "it's like you're living in a state of jet lag during the work week," said Klerman, who was not involved in the study.
Over 46% of the survey participants reported at least 1 hour of social jet lag, while 19.3% experienced at least 2 hours.
"With strict work schedules and jam-packed weekend activities, it's not surprising that many individuals report that their sleep needs are not being met during the week," said sleep specialist Dr. Raj Dasgupta, a clinical associate professor of medicine at the University of Southern California's Keck School of Medicine. He was not involved in the study.
Untreated social jet lag can have serious consequences, including insomnia, early waking or excessive sleepiness, daytime fatigue, difficulty concentrating, constipation or diarrhea and increased cortisol levels. It may also play a role in the development of obesity, type 2 diabetes and heart disease.
A June 2021 study analyzed the sleep habits of 85,000 people in the UK and found those people with a misaligned sleep cycle were more likely to report depression, anxiety and have fewer feelings of wellbeing.
While the JAMA study did not examine if people preferred mornings or evenings, it is the "night owls" who prefer to stay up late that will suffer most, Kolla said: "These are the folk who are likely going to have more of a sleep debt and more social jet lag due to this mismatch between their internal body clock and current work requirements."
To overcome sleep deficits and social lag, experts suggest backtiming your bedtime from your morning alarm. If you need to be up by 6 a.m., you'd want to go to sleep by 11 p.m. to get the recommended seven hours of shuteye needed to refresh your body.
Tips to help with falling asleep quickly include meditation, deep breathing and progressive muscle relaxation. Then, to keep your internal clock running smoothly, it's also best to keep to the same schedule on non-work days.
"You should try and have the same sleep and wake times on weekdays and non-work days," Klerman said. "But if you aren't getting enough sleep during the work week, you should try and get more on your free days."
Research over the last few years is finding "catch-up sleep" is helpful, she said: "For example, a 2020 study found adults who caught up on sleep on their free days were less likely to show higher inflammation levels." Inflammation is a key contributor to chronic disease.
A 2019 study that followed almost 44,000 people for 13 years found that for people under 65 sleep of less than 5 hours on free days was associated with a 52% higher premature death rate. However, longer sleep of about 9 hours on off-days was not.
One 2017 study of Korean adults found that catchup sleep on free days may be linked to lower weight, while another 2017 study found sleeping an additional hour on non-work days also helped control blood sugars.
Other tips to counter sleep deficits include exercising, avoiding naps and practicing good sleep hygiene, such as avoiding coffee in the afternoon and alcohol at night, keeping smartphones and other electronic devices out of the bedroom and taking a warm bath or relaxing with yoga.
Then, when you get up in the morning, "don't hit that snooze button," Dasgupta said. "Try your best to get out of bed when your alarm goes off and try to get outside; especially if the weather is good and there is a lot of sunshine in the morning. This will allow suppression of melatonin and reset that circadian rhythm."