When deadlines and exams pile up, sleep is often the first thing students cut. It feels like a sensible trade: more hours awake means more hours to study. The research says otherwise.
How much sleep you need
Adults aged 18 to 60 should get 7 or more hours of sleep a night, and teenagers aged 13 to 18 should get 8 to 10 hours, according to the U.S. Centers for Disease Control and Prevention, which bases its guidance on recommendations from sleep medicine experts. Many students regularly get much less.
What sleep does for learning
Researchers have found that sleep after learning helps consolidate new memories — stabilizing them and strengthening them so they’re less likely to be forgotten (Diekelmann & Born, 2010). Sleep before learning matters too: when you’re short on sleep, it’s harder to pay attention and take in new information in the first place.
In other words, sleep supports both ends of studying: getting information in and keeping it there.
Too little sleep also affects things you need in an exam room: attention, reaction time, mood and the ability to think clearly about unfamiliar problems.
The trouble with all-nighters
An all-nighter before an exam combines the worst of both:
- The material you cram that night doesn’t get a night of sleep to consolidate it.
- You walk into the exam tired, with weaker attention and slower thinking.
- The following days are often lost to recovery, which can affect your next exam or deadline.
If you’re short on time, a better trade is usually to study until a reasonable hour, sleep, and do a short review session in the morning.
How to sleep better during busy weeks
- Keep a regular schedule. Going to bed and getting up at roughly the same time every day, weekends included, is one of the most effective habits for better sleep.
- Watch the caffeine. Caffeine stays in your system for hours. Try to have your last coffee, energy drink or caffeinated tea by early afternoon.
- Wind down. Give yourself 30 to 60 minutes before bed without studying. Dim the lights and put your phone away or out of reach.
- Keep your bed for sleep. If you study in bed, your brain starts to link it with work. Use a desk when you can.
- Nap carefully. A short nap of about 20 minutes can help with alertness. Long naps, or naps late in the day, can make it harder to fall asleep at night.
- Go easy on alcohol. It may help you fall asleep, but it disrupts your sleep later in the night.
When to get help
Occasional bad nights are normal, especially around exams. But if you regularly can’t fall asleep or stay asleep, feel exhausted despite spending enough time in bed, or snore heavily, talk to a doctor or your campus health service. Sleep problems are common and often treatable.
Stress and low mood often show up as sleep problems first, and campus counseling services are there for exactly that. If you’re in crisis in the U.S., call or text 988 to reach the 988 Suicide & Crisis Lifeline at any time. Outside the U.S., Find A Helpline lists free helplines by country.
Frequently asked questions
How much sleep do college students need?
Adults aged 18 to 60 should get 7 or more hours of sleep a night, and teenagers aged 13 to 18 should get 8 to 10 hours, according to the U.S. Centers for Disease Control and Prevention.
Is it better to sleep or study the night before an exam?
Usually sleep. Sleep helps consolidate what you have learned and keeps your attention and thinking sharp for the exam. A better trade than an all-nighter is to study until a reasonable hour, sleep, and review briefly in the morning.
Are naps good for studying?
A short nap of about 20 minutes can help with alertness. Long naps, or naps late in the day, can make it harder to fall asleep at night.
When should I stop drinking caffeine?
Caffeine stays in your system for hours, so try to have your last coffee, energy drink or caffeinated tea by early afternoon.
