When your body says, "sleep," but your anxiety says, "not until you finish this last bit of work," sometimes your mind gets the best of you. The next thing you know, it's morning, and you've pulled an all-nighter. Whether you're a student, a busy parent, a burnt-out employee, or some combination of all of those things, chances are you've been in this situation.
The morning after an all-nighter, you feel like a shell of yourself: it's harder to concentrate, make decisions, respond to impulses, and think creatively when you're sleep deprived. From a scientific standpoint, this all makes sense, because your body needs sleep to function, even down to a cellular level.
A 2015 study in the journal PLOS One showed that a night of missed sleep can lead to structural changes in the brain. Another 2017 study out of the University of California Los Angeles found that sleep deprivation disrupts brain cells' ability to communicate, which is why you experience so many "mental lapses" after a sleepless night. The hormone cortisol also follows a specific pattern overnight, but without sleep, cortisol can't drop, and your body will feel confused the next day. And finally, we also know based on animal studies that, over time, sleep deprivation can increase buildup of a protein that's associated with Alzheimer's disease. So, sleep is a pretty big deal.
A good night's sleep is a reset process for the brain and body the next day, says Alexis Halpern, MD, emergency medicine physician at New York-Presbyterian/Weill Cornell Medical Center. "Sleep allows the body’s cells to reenergise, and the brain to clear waste and toxins from the day, and make space for memories and learning," she says. Most of the time, pulling an all-nighter is not worth it, because you'll feel both miserable and moody the next day. But sometimes, an all-nighter really is necessary.
As an emergency medicine doctor, Dr. Halpern has experience staying up all night to work a night shift in the ER. She believes you can never really "catch up" on sleep, but there are a few things she does it make her necessary all-nighters less miserable. The day before an overnight, Dr. Halpern will sleep as late as possible into the afternoon, then try to do some light exercise to get her body energised. "I eat light meals, and I only drink coffee right before I go in," she says. "I definitely avoid a heavy dinner and make sure to bring a lot of snacks — preferably healthy, because a sugar rush overnight leads to a terrible crash at a time the body wants to be asleep." Afterwards, she'll come home and sleep until the afternoon, then try to go to bed at a normal time.
While the health effects of shift work are complex, Dr. Halpern says it can take a few days to get back on track with a sleep schedule like hers. Even so, she doesn't recommend pulling an all-nighter if you have the choice. No matter how stressed you are, it's important to remember that sleep is more than just a break from your work, it's a complex and necessary biological process. Bottom line: You're probably better off doing a little less work and getting a little more sleep, she says.