Common Reasons Why You Wake Up at 3 a.m.

Asking yourself why you keep waking up in the middle of the night? Here are some of the common causes for those 3 a.m. wake-ups.

Insomniac young woman in bed
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See if this sounds familiar: You wake up in the middle of the night and look at your phone to check the time…but you already know it’s nowhere close to time to wake up. It’s 3 a.m. Or maybe it’s 4 a.m. or 2 a.m. or even just midnight.

You’re not alone. According to many sleep medicine specialists, one of the most common questions they get asked is: Why do I keep waking up at 3 a.m. and what can I do about it?

Overnight awakenings — commonly referred to by sleep scientists as wake after sleep onset — are a frequent occurrence. One study found that more than one-third of us wake up in the middle of the night, three or more nights per week.

The good news is that nighttime awakenings are usually nothing to worry about — as long as you’re able to easily fall back asleep. In fact, according to Jenna Gress Smith, Ph.D., a clinical health psychologist specializing in sleep medicine, most people wake up several times during the night, sometimes without remembering.

But if you are regularly waking up, and feeling that your sleep quality is impaired because of those awakenings, it is worth looking to pinpoint the reason.

Explanations for waking up in the middle of the night

First, separate the time of your wake-ups from the cause. Even if the timing of those wake-ups is surprisingly precise — the same window, night after night — the time itself really isn’t significant, says psychologist and sleep specialist Alexa Kane. There are, however, a few common reasons why it may be happening, and figuring out the cause can help provide the solution.

Anxiety, worry, and stress

Stress is the body’s mental and physiological response to a perceived threat, likely to rear up when we feel anxious, worried, under pressure, overwhelmed, or in danger.

“When you feel stressed, your brain kicks into fight-or-flight mode, flooding your body with hormones including adrenaline and cortisol to prepare you to fight, flee, or freeze,” says Gress Smith. “That response can trigger an array of physical symptoms, such as a quickened heart rate, dizziness, or a dry mouth.”

Cortisol may be best known as the body’s stress hormone, but it also plays a pivotal role in managing our sleep “architecture.” Studies of circadian rhythm — your 24-hour body clock — have shown that cortisol levels naturally begin to increase between 2 and 3 a.m. If you’re already stressed or anxious, and your cortisol levels are naturally rising, it’s not surprising that you’d wake up at that hour. When your body’s sympathetic nervous system kicks into gear, the increase in heart rate and blood pressure also may make it harder to fall back asleep.

Adding to the physiological reaction, if something is on your mind, the middle of the night — when there are no distractions or regular to-do’s — is a common time to fret about worries, which can amplify your body’s stress response, making it harder to stay asleep or get back to sleep.

How to stay asleep when stressed:

One important way to encourage sleep when you’re stressed or anxious, is to account for those stresses before bed. Outside the bedroom (so that you don’t associate your bedroom with stressors), sit down and make a list of all items on your to-do list, and all stresses to face in the morning. Plan time the following day to confront those items, and tell yourself that you’ve designated time and brain space to them during waking hours. Called a “mental litter box,” by Jade Wu, Ph.D., Sleep.com sleep advisor and author of Hello Sleep, this method can help give you a psychological blank slate for bed.

If you’ve awakened in the middle of the night, the key to falling back asleep is encouraging a transition from a state of anxiety or frustration to relaxation, says Gress Smith. The calmer you are, the easier it’ll be to fall back asleep. Relaxation techniques like deep breathing, progressive muscle relaxation, and guided meditations can help quiet your mind and calm that fight-or-flight response so you can drift off.

Low blood sugar

Depending on your meal schedule, the solution could be simple. “The first question I ask [my patients] is, ‘When was the last time you ate?’” says Michael Breus, Ph.D., a psychologist who specializes in sleep disorders. “Often, they’ve finished their last meal at 7 p.m.; now it’s 3 in the morning — that’s eight hours later — so guess what? They’re out of fuel.” When your brain senses your tank is close to empty, it spikes cortisol to help jumpstart the metabolic process, get you hungry, and wake you up to eat. “That can be part of what’s going on,” says Breus.

How to stay asleep when cortisol spikes:

“Don’t go to bed hungry,” says Breus. The opposite is also true, though: Don’t go to sleep with a full belly — the body isn’t meant to digest food lying down — but you don’t want to be starving either. For those who are eating too early, a thoughtful late snack could help. “About 30 minutes before bedtime, think about having a 250-calorie snack that’s 70% complex carbs and 30% protein. An apple with some nut butter would be perfect. Or a non-sugary cereal like oatmeal with some almond milk,” Breus advises.

For those who don’t want a proper snack, a simple teaspoon of raw honey could help, Breus suggests. “I’ve found that raw honey is difficult for the body to metabolize and helps keep your blood sugar stable longer. Many of my patients can make it through the night simply with a teaspoon of honey before bed.” As a bonus, locally sourced raw honey can help with seasonal allergies.

If you have diabetes, it’s a good idea to check with your doctor to make sure your blood sugar is properly controlled throughout the night. Waking up could signal that your hormones or blood glucose levels are fluctuating.

Shifts in sleep cycles

Nighttime sleep involves multiple sleep cycles and transitions between lighter and deeper sleep stages. “The length of each stage varies throughout the night, with longer deep sleep earlier in the evening and longer REM sleep — lighter sleep when dreams occur — as morning approaches,” says Gress Smith. “Your arousal threshold — how easy it is for something to wake you up — varies depending on what sleep stage you’re in.” Lively dreams, for example, could rouse you as you transition between sleep stages.

“REM is your lightest stage of sleep — your brain is very active and your body moves around more. When you transition from light sleep into REM sleep, you may wake up more easily,” Gress Smith explains. “Depending on when you fall asleep, [the overnight wakeup] may be the point between two sleep cycles and just a vulnerable spot.” When babies are small, they’ve not learned to connect sleep cycles, which is part of the reason why overnight awakenings are so common for babies.

Another reason you may consistently wake up at 3 a.m. on the dot is from conditioning, adds Gress Smith. Your body and mind love patterns and routines, so if they get used to waking up at a certain time, it may continue out of habit.

How to stay asleep between sleep cycles:

During lighter sleep, you’re more apt to wake up from environmental factors like noise from a passing truck or your bedroom being too hot or stuffy. Ideally, your bedroom should be dark, comfortably cool, and quiet. Consider using earplugs or an eye mask to block out unwelcome environmental disruptors, and adding a fan, lowering the thermostat, or even cracking the window to keep the room at the right temperature.

Interestingly, says Wu, between 2 and 3 a.m. is also when your core body temperature, which is determined by your circadian rhythm, stops dropping and starts rising again ahead of your wake-up, which also puts you in a slightly lighter phase of sleep. “If your room isn’t nice and cold, you’re almost assured to wake up,” she says.

Insomnia

“Everyone wakes up multiple times per night,” says Wu. “It’s very common for people to wake up around 2 or 3 a.m. because this is when our sleep architecture (the pattern of our sleep stage cycles throughout the night) naturally has a shift from more deep sleep to more REM sleep. People with insomnia also experience this but are more likely to stay awake for a long time or feel anxious about waking up.” This negative feedback loop can create pressure, as nervousness about staying asleep can lead to feelings of pressure and stress when you find you have, indeed, woken up overnight.

How to address insomnia and stay asleep:

There is some overlap with the treatment of anxiety. “Don’t put too much pressure on yourself to stay asleep or get back to sleep,” Wu says. “It’s okay to be awake during the night, and waking up doesn’t mean you’re ‘starting over’ with your sleep.” Historically, people used to sleep in two segments, known as biphasic sleep, when the moonlight could facilitate overnight activity. “During this natural intermission [between the two sleep segments], they’d do chores, socialize for an hour or so before going back to bed. There’s nothing wrong with this as long as you’re getting enough sleep overall.” Author Roger Ekirch argues in his book At Day’s Close: Night in Times Past that we may naturally divide our sleep into those two blocks. For many people, their anxiety about the awakening is far more problematic than the awakening itself. People wake up. Have a plan for what you do if it happens to you.

If you’re fully awake for a while and you get frustrated, Wu suggests getting up and doing something enjoyable so you’re not agonizing and associating your bed with feelings of frustration. If the awakenings become frequent and severe, see a behavioral sleep medicine specialist or other insomnia expert.

Medications

Certain medications used to treat health issues — anti-inflammatory corticosteroids, SSRI antidepressants, beta blockers to treat blood pressure, even some cold and allergy medications — can disrupt your sleep patterns and cause nighttime awakenings, says Dr. Chris Winter, Sleep.com advisor, neurologist, and author of The Rested Child and The Sleep Solution and host of the podcast Sleep Unplugged with Dr. Chris Winter.

It’s important to review medications with your doctor, for side effects and sleep issues.

How to stay asleep when on stimulating medications:

If you think your meds are keeping you up, Winter suggests giving your healthcare provider a call. They may be able to prescribe an alternative drug, alter your dosage, or figure out a better time to take your meds. For instance, you might be able to take your medication in the morning or earlier in the day to help alleviate sleep disturbances.

Aging: You’re getting older

With age comes wisdom, but also more early morning awakenings. “As you get older, you spend less time during the night in the deepest sleep stage, which can lead to more nighttime awakenings,” Wu says. “Also, your circadian rhythms shifts so you get sleepier earlier in the evening and also naturally wake up earlier in the morning, so it’s not uncommon for people in their late 60s and beyond to wake up hours before sunrise.”

Older people are also more likely to report nighttime bathroom breaks, thermal regulation issues, and overall aches and pains while sleeping.

How to stay asleep as you get older:

Getting daily physical activity is important at every stage of life but especially as you age. Extensive research shows that any type of exercise, even a daily walk, can help alleviate sleep-related problems and improve the quality of your sleep.

“Haphazardly napping during the day, even if it’s falling asleep in front of the TV for 10 minutes or taking catnaps here and there, can lead to disrupted sleep at night,” says Wu. “This not only decreases your sleep drive (your ‘hunger’ for sleep) but can also disrupt your circadian rhythms. So your melatonin curve (the increase and decrease pattern of melatonin during the 24-hour day) is flatter, making your days more sleepy and your nights more awake.”

To help strengthen your circadian system, get lots of light exposure during the day, and stick to consistent meal and bedtime/wake-up routines.

Other reasons you’re waking up

A few other things that can disrupt your sleep:

Eating a big meal too close to bedtime

That late-night meal will keep your digestive system working hours after you’ve eaten, which isn’t conducive to restful sleep. It’s best to eat about three hours before going to bed, says Winter. That will give your body time to process every last morsel.

Caffeine too late in the day

In general, most sleep experts say to cut out all caffeine about eight hours before going to bed. If you need that boost, be sure to finish three hours before bed at the very latest.

Nighttime bathroom visits

Nocturia is the medical term for waking up two or more times during the night to use the bathroom. About 1 in 3 adults over the age of 30 experience this condition. If you notice you’re up and down a lot, it’s a good idea to speak with your healthcare provider. Sometimes it’s just a matter of cutting back on fluids before bed.

Sleep disorders

Issues such as Obstructive Sleep Apnea, Periodic Limb Movement Disorder, and other parasomnias are known for middle-of-the-night issues. “Sometimes the awakenings can indicate a disorder of sleep continuity,” says Winter. Usually one awakening is OK. If you’re getting your best reading done in the middle of the night, it may be time to investigate the problem.

Medical conditions

Gastroesophageal reflux disease (GERD), neurological disorders such as Parkinson’s disease, dementia, and heart and vascular conditions are associated with less deep sleep and more interrupted sleep, says Winter.

Menopause

A rise in nocturnal awakenings (with or without hot flashes) is a common sign of perimenopause and menopause. “Hormone treatments can offer some women relief and improved sleep,” Winter says.

When Does Waking Up in the Middle of Night Become an Issue?

“If you’re frequently experiencing long stretches of awake time during the night [and you’re not achieving your target overall amount of sleep], it’s probably a good idea to speak with a behavioral sleep medicine specialist or other healthcare provider who specializes in insomnia,” says Wu.

How to improve your sleep

  • Increase your daylight exposure, preferably early in the morning. Light helps set your circadian rhythm and encourage better sleep at night.
  • If you exercise, do it in the morning, when you’re getting that morning light exposure — this will help your body recognize that it’s time to be awake.
  • Try to remain consistent with your timing, including when you go to sleep, when you wake up, and when you eat your last meal of the day.
  • Limit your bed to only sleep and sex, which includes doing your TV-watching and your over-night awake time elsewhere. The more your body associates your bed with only sleep, the better your physiological reaction will be to getting into bed.

Are you trying to get more sleep than you need?

 “For many people, awakening during the night is a sign that they are seeking too much sleep,” Winter says. “Just because you spend 11 hours in bed doesn’t mean you can sleep 11 hours. Often the awakening is a subtle hint that your expectations are a little too high when it comes to the number hours of sleep you need.”

Keep in mind that some sleep researchers think that an awakening in the night might be perfectly normal, says Winter, and its presence does not necessarily represent a problem, but if the awakening is stretching into extended periods and causing you anxiety, it is worth investigating.