You wake up, for no apparent reason, at 5:03 a.m.—and your alarm is set for 6.
Do you take advantage of an early start on the day or try to catch some more sleep?
The best answer depends on a few factors, experts tell Fortune, but generally leans toward heading back to bed. That’s because sleep has restorative properties and impacts multiple body systems.
Sleep or stay up?
The first question to ask yourself: whether or not you’ve gotten the recommended seven to nine hours of shut-eye. That’s according to Joachim Behar, a sleep researcher and the head of the Technion-Rambam Center for Artificial Intelligence in Healthcare in Haifa, Israel.
Most experts recommend 7-9 hours of sleep for adults. If you haven’t deposited enough time in your sleep bank for the night, Behar suggests heading back to bed—with one exception. If your alarm is set to wake you in 90 minutes or less, stay up, he advises. A complete sleep cycle takes around 90 minutes, and interrupting one can lead to sleep inertia.
That’s “the grogginess and difficulty concentrating that many people feel after waking up,” Dr. Raj Dasgupta, associate program director of sleep medicine fellowship at the University of Southern California, tells Fortune.
Waking up early isn’t always a bad thing, Dasgupta maintains. If you’re finding yourself staring at the ceiling 30 minutes or less before your alarm, “it’s a good sign that your sleep schedule is aligned with your circadian rhythm,” he says.
‘Relaxation is almost as good as sleep’
Another approach to the conundrum: Ignore the time altogether and rely solely on your alarm. Dasgupta recommends covering your clock or putting your phone out of reach, if you use it to check the time at night.
“If the alarm hasn’t gone off yet, it’s still nighttime, and that’s all you really need to know,” Dasgupta says.
Even if you can’t fall back asleep fully and drift in and out of consciousness, you’re likely getting more shut eye than you think. What’s more, “relaxation is almost as good as sleep,” he advises.
“If you can’t sleep, lying restfully is the next best thing,” he says. “It may give you some of the benefits of meditation”—and is certainly better than laying in bed stressing over the matter.
Why does getting enough sleep matter?
How you feel when you’re awake partially depends on what happens when you’re sleeping, according to the CDC. When you sleep, your body performs work that supports healthy brain function and physical health. And for children and teens, getting enough sleep aids healthy growth and development.
Adequate sleep supports the following body functions, the CDC says:
- Heart and circulatory system: People who don’t sleep enough or wake up often may have a higher risk of heart disease, high blood pressure, obesity, and/or stroke.
- Metabolism: Not getting enough quality shut eye may lead to insulin resistance, increased eating (especially of unhealthy foods), and decreased physical activity, all of which contribute to obesity, which carries its own health risks.
- Immune systems: A particular type of immune cell works harder when you sleep. That’s why those who don’t get enough sleep may get sick more often.
- Cognition: Sleep aids in learning and forming long-term memories. Those who don’t get enough high-quality sleep might have problems focusing and thinking clearly.
Copious medical studies support the need for adequate sleep, and quality sleep. Cases in point:
- People who get less than five hours of sleep each night are more than three times more likely to have a stroke than those who get the recommended seven hours, according to a study published in April in the journal Neurology.
- People who struggle to fall asleep and stay asleep may also be at a greater risk of a stroke, according to research published in June in the journal Neurology.
- Early Alzheimer’s disease in those predisposed to the condition may be worsened by sleep apnea, according to a study published in May in the journal Neurology.
Tips for getting good sleep
If you’re consistently falling short of the 7-9 hours of nightly sleep goal, consider an earlier bedtime, Dasgupta recommends. He also recommends improving “sleep hygiene,” a phrase that refers to habits and conditions that can help you get a good night’s rest.
Some tips from both Dasgupta and Behar:
- Aim to go to bed and wake up at the same time every day, even on weekends.
- If you wake up in the middle of the night and you’re unable to fall back asleep, try some deep breathing exercises or meditation.
- If this doesn’t work after about 20 minutes, move to another room and do something distracting in dim light until you feel sleepy again.
- Cultivate a tranquil bedtime ritual, which includes limiting the following during the hours immediately leading up to bedtime:
- Screens like TVs, computers, smart phones, and tablets
- Large meals, caffeine, alcohol, and nicotine
- Vigorous exercise (exercise can promote restorative sleep, but too much too close to bed can be counter-productive)
“Simple things like coziness are important too,” Behar says. “A sleeping space with minimal noise, darkness, and optimal temperature, and comfortable sleep accessories like a good mattress and pillows promote good sleep hygiene.”
Everyone has an off night of sleep now and again, according to Dasgupta. But those who routinely wake up hours before their alarm is set should consult their doctor or a sleep specialist, as they might have a sleep disorder like insomnia or sleep apnea, he says.
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