Recovering from sleep deprivation takes far longer than you think

All of us occasionally suffer from sleep deprivation. Maybe it was a late night out, a blockbuster study session, a red-eye flight, or a few straight nights of tossing and turning in bed. Whatever the reason, we all occasionally suffer the sapping consequences of sleep deprivation. But we take solace in knowing that there’s a cozy cure: a good night’s rest.

Unfortunately, solving sleep deprivation may not be so simple. While extra rest does indeed remedy this frequent diagnosis, recent studies suggest that returning our mental and physical functions to full capacity takes more time than thought.

The consequences of sleep deprivation

Adults generally need between seven and eight hours of sleep each night — any less and your health is liable to suffer. After a night or two of poor rest, you might feel foggy, irritable, and anxious, even a little hungry as the body tells you it is short on energy. Meanwhile, attention, short-term memory, focus, and other areas of cognitive performance also take a hit.

Chronic sleep deprivation — when you consistently get less rest than what you require — has more pernicious effects. Memory and learning suffer even more: Sleep is when the brain consolidates information after all. Blood pressure and heart rate tick higher. Immune functions fall. Metabolism slows, leading to weight gain. Inflammation rises. Brain cells die from overwork. All of these physiological effects seem to lead to a higher risk of cardiovascular disease and dementia.

Often, those suffering from short-term or chronic sleep deprivation won’t even be aware of their mental deficits. Studies show that subjective feelings of sleepiness and mood can recover after a night of normal sleep, and can even return to baseline when someone grows accustomed to long-term inadequate rest.

But again, bodily dysfunction remains. In a 2021 study, subjects slept an average of 5.3 hours for ten nights and then were given a week to sleep as long as they liked. While they felt normal after that week of unrestricted sleep, their cognitive function did not totally return to baseline levels before their sleep deprivation.

Recovering from sleep deprivation

Research suggests that the only way to recover completely is to get the amount of sleep you need for an extended period of time. Relieving short-term sleep deprivation might take days or even a week. For chronic sleep deprivation, full recovery may take weeks or months.

Sleep researchers sometimes call this process “repaying” one’s “sleep debt.” For example, if a person who needs eight hours of rest per night only gets five hours on a particular night, it will take six days of 8.5 hours of sleep to “repay” those three lost hours. The math of sleep debt means that you usually can’t nap your way out of persistent sleep deprivation. After all, most people lack the time for long naps during the day. What’s more, naps can make it harder to fall asleep at night, especially if taken later in the afternoon.

It also seems that you can’t simply make up for lost sleep during the week by sleeping in on the weekends. A 2019 study found that subjects who had their sleep slightly reduced during the week but slept an hour longer on weekends still suffered adverse metabolic effects. Research published earlier this month found that subjects with this sleep arrangement also had elevated heart rates and blood pressures.

Not getting enough sleep at one time or another is an inevitable part of modern life, so the best way to mitigate its draining effects and recover quickly is to practice salubrious sleep habits. Exercising often (not too close to bedtime), keeping a regular bedtime, eating a proper diet, and avoiding electronic screens and other sources of artificial light an hour before attempting to sleep can all help you doze off quickly and stay asleep.