The phrase “sleep debt” conjures an image of a ledger listing the number of hours you’ve recently spent asleep. A night of restful sleep puts you in the black, but any night where you don’t log enough quality zzz‘s tips you into the red. Theoretically, that would make it seem like you’d just need to sleep more on the nights following a sleep deficit in order to break even again. But according to sleep doctors, sleep debt doesn’t quite work this way—and it isn’t easily paid off in this fashion, either.
“Sleep debt occurs when you’re not getting enough opportunity to sleep compared to your body’s current needs,” says sleep psychologist Jade Wu, PhD, sleep advisor for Mattress Firm. While adults generally need somewhere between seven and nine hours of sleep each night, the exact number can fluctuate based on your daytime activities. For example, if you do a high-intensity workout one day, you may need more sleep than usual that night. So, if you sleep for your usual amount of time (say, seven hours) and you’re still tired the next day, you’re likely coming up short—meaning, you are accumulating sleep debt.
“Sleep debt occurs when you’re not getting enough opportunity to sleep compared to your body’s current needs.” —Jade Wu, PhD, sleep psychologist
But unlike other types of debt, a sleep deficit created by depriving your body of sleep for a few consecutive nights typically can’t be remedied by simply making up for lost sleep. (After all, if you’ve accumulated 10 hours of sleep debt during the course of the workweek, it’s probably not feasible for you to sleep an additional 10 hours on top of your usual sleep to make up the difference over the weekend.)
Below, sleep doctors break down the often-misunderstood concept of sleep debt and share their best advice for getting ahead of it.
Why paying off a sleep deficit isn’t as simple as sleeping in on the weekend
The most common misconception about sleep debt is the idea that you can erase the deficit by sleeping in for a certain number of hours, says pulmonologist and sleep-medicine specialist Raj Dasgupta, MD. As noted above, it isn’t typically possible, nor a smart idea, to try to sleep for several additional hours in order to account for the hours of sleep you’ve recently lost.
Also, this kind of additional sleeping won’t reverse the effects of sleep deprivation, anyway. “When you are sleep-deprived, even if you sleep extra the next day, the clinical manifestations linger for days afterword,” says Dr. Dasgupta. Translation: You could still feel groggy, moody, or just not fully with it for a couple days after losing sleep, even if you try to make it up.
That said, allowing your body to sleep “just for as long as it wants to sleep,” when you can (like on a weekend) can allow you to pay off some of that sleep debt, says Dr. Wu. After all, sometimes, your body is just hungry for a little more sleep than you can reasonably feed it during the workweek, and catching up a bit can help.
Even so, Dr. Wu and Dr. Dasgupta say that this isn’t a great fix long-term because it requires you to shift your sleep schedule and adopt a later wake-up time throughout the weekend, which can have the effect of jet lag, making it tougher to fall asleep at your usual time come Sunday night. (It’s for that reason that sleep experts don’t recommend sleeping in any longer than about an hour on the weekends.)
How to actually mitigate sleep debt and get back on track with your sleep
If you find that you are regularly accumulating sleep debt during the week, try to fit a short nap into each afternoon, and aim to go to bed earlier on weekends. Ideally, that allows you to keep your wake-up time consistent across both weekdays and weekends, which is key to maintaining your circadian rhythm. “What you want to do is set the anchor of when you get up in the morning at the same time because that’s the strongest signal to your circadian clock to stay steady,” says Dr. Wu. Changing your bedtime is less of a detriment to that clock, she adds, so it’s better to adjust on that end if need be.
Beyond these adjustments, there isn’t much can do to actually make up for lost sleep. As noted above, it’s a misconception to think that you can just knock out all your sleep debt by sleeping for the full length of time that you’ve deprived yourself. It’s for that reason that Dr. Wu thinks we need to reframe the concept of sleep debt entirely.
“The term ‘sleep debt’ is both too scary and not scary enough,” says Dr. Wu. On the one hand, the health detriments of not getting enough sleep are widely known, and it’s important to be proactive about getting enough quality sleep each night. But on the other hand, the idea that you can never really pay off a sleep deficit may feel super unnerving. Instead, it’s best to banish the all-or-nothing thinking and land somewhere in the middle. The truth? Sleep is flexible, and our bodies are resilient and can adjust when we have slip-ups.
While you can’t necessarily gain back sleep you didn’t get, you can set a better path forward. Rather than stress over lost sleep—which can, paradoxically, make it harder to fall asleep the next night, worsening your sleep deficit—focus on practicing good sleep hygiene whenever you can.
That starts with listening to your body and going to bed when you’re tired. If there are outside forces preventing you from being able to do that, see where you can make adjustments in your schedule to prioritize your sleep. In addition to setting a bedtime and a wake-up time, consider creating a bedtime routine to ensure you actually abide by that bedtime, and again, taking short power naps in the afternoons to nix daytime tiredness. Following these steps will help ensure that you’re getting enough high-quality sleep on the regular—so, you don’t run the risk of racking up sleep debt in the first place.
