the case for sleeping in, sleep debt

The Right Way to Sleep In

There's a science to making up for late nights.

It seemed like a brilliant idea at the time, to make a big push for a work deadline, with barely five nightly hours of sleep all week. On Friday, you decompressed over wine, dinner, and multiple episodes of Game of Thrones until 1 a.m. On Saturday and Sunday you slept in until noon—that’s four extra hours of slumber, on top of the recommended seven, each day. Net sleep debt: zero. So why is your head still in a fog? The truth is, those eight additional hours over the weekend don’t necessarily make up for the eight hours lost during the week.

Sleep math doesn’t work that way. “People concentrate an awful lot on how much we sleep, but the quality of sleep is equally important,” says Jim Horne, Ph.D., professor emeritus of psychophysiology at Loughborough University in the UK, and author of SleeplessnessSometimes the decisions you make before ever setting foot in the bedroom can make a difference in how you feel in the morning (or afternoon). Here, six steps that could help you sleep your way back into fighting form.

Put together a grain bowl for dinner: Earlier this year, Columbia University researchers reported that high-fiber foods are associated with enhanced slow-wave sleep—that truly restorative time of night, when your muscles take in a surge in blood supply, tissues receive repair, growth hormones are released, and your immunity gets boosted. In contrast, fatty foods and refined carbohydrates rob you of this prolific portion of sleep, and your already tired body gets short shrift. Your best bet is to have a well-balanced meal, says Marie-Pierre St-Onge, Ph.D., associate professor at Columbia University Medical Center, and the study’s lead author. If you’re having protein, make it lean, and include whole grains and vegetables.

Skip the nightcap: As everyone has heard by now: alcohol dependably sends you snoozing, but leaves you staring at the ceiling come 3 a.m. Even worse, it cheats you out of quality slumber in the latter portion of the evening, so you’re short on REM sleep, the dream stage that promotes memory and learning.  

Bring on the mood lighting: As the sun goes down, melatonin rises, and our drive for sleep goes up. Bright lights delay that increase in melatonin, and you feel as if you’re able to stay up later than you should. But just because you don’t feel sleepy doesn’t mean you don’t need to catch up on sleep. To get in sync with your biological clock, pull down the shades and dim the lamps.



Settle into a good old-fashioned book: In a 2014 PNAS journal study, subjects who read on digital devices took longer to fall asleep and felt sleepier the next day, even after eight hours of shut-eye, compared to a control group who read on paper. Blue light not only suppresses melatonin, it reduces your amount of REM sleep. Give Netflix and your digital gadgets a rest, so you can, too.

Go to bed as soon as you can: Humans are primed to sleep when it’s naturally dark. Individual variations exist, but essentially, says Allison Brager, Ph.D., a sleep scientist with Walter Reed Army Institute of Research, “We’ve evolved to be day-active creatures.” Drastic, chronic shifts to our circadian rhythms wreak havoc on them: Expecting to show up at work by 9 a.m. after a weekend of sleeping in till noon is like jet lag (except you haven’t gone anywhere exotic)—or shift work, which, over time, has been shown to wreak havoc on memory, how fast you think, and cognition in general. “Sleep during the day looks different than at night,” says Elizabeth Klerman, M.D., Ph.D., associate professor of medicine at Harvard Medical School. By all means, sleep into the afternoon if that’s the only time you can, but otherwise, why stay up late when you don’t have to? “You need tell yourself ‘I’m worth it,’” she says. “It’s the easiest thing to do and it will make you feel better."

Pay back debt over several days: If you’re a night owl, take baby steps, says Scott Kutscher, M.D., a sleep specialist at The Stanford Center for Sleep Sciences and Medicine. On Friday and Saturday, set your alarm close to your weekday wake-up time, but turn in a little earlier (even 15 minutes will add up over time) than when you’re typically capable of falling asleep. Naps can help, too; keep them at 20 minutes or less to avoid feeling groggy afterward. Not only will they make you feel more alert and nimble immediately upon waking, they’ll count toward your total sleep hours. The whole process may take several days to pay back your sleep debt, but you’ll make that time in bed really count.