Snooze alarms may cost you vital sleep — three experts weigh in on the habit

CNN

6 days ago

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When jolted awake by the blare of an alarm clock, it's tempting to reach for the snooze button to catch a bit more shut-eye. In my case, 'just five more minutes' is practically a morning mantra. And what's the harm?
There's increasing debate about your snoozing habit, and whether or not it's silently sabotaging your morning.
On the 'stop snoozing' side of the research, sleep scientist Dr. Rebecca Robbins suggests the snooze alarm may actually cost us sleep.
'That first alarm may interrupt vital stages of sleep, and anything that you might be able to get after hitting the snooze alarm is probably going to be low quality and fragmented sleep,' said Robbins, an associate scientist for the Division of Sleep and Circadian Disorders at Brigham and Women's Hospital.
The average snoozer takes an extra 11 minutes after their first alarm, according to a new study coauthored by Robbins that used data from the sleep-tracking app SleepCycle. That adds up to about one night's worth of sleep per month spent snoozing.
As we sleep, the brain cycles through different stages of neurological activity and the second half of the night is dominated by rapid eye movement (REM) sleep, when most of our dreaming is thought to take place. It's an important sleep stage for our cognitive function and memory consolidation, said Robbins, who is also an assistant professor of medicine at Brigham and Women's Hospital.
'When you press the snooze button, especially for just a few minutes at a time, you're not likely to return to that REM stage,' Robbins said.
But for a different take, there are sleep experts like Dr. Justin Fiala, a pulmonary, critical care and sleep medicine physician at Northwestern Medicine Canning Thoracic Institute.
There isn't consensus on whether this lighter sleep achieved during a snooze session always does more harm than good, said Fiala, who is also an assistant professor at Northwestern Medicine.
On one hand, losing out on quality sleep instead of just waking up later may increase the risk of cognitive impairment and lower one's mood.
'Certainly, if you're feeling worse off (and) more tired from the snooze alarm, I would recommend going back to waking up cold turkey without it,' said Fiala, who also runs the CommunityHealth Chicago sleep clinic.
On the other hand, those with a certain chronotype — a natural disposition determined by factors such as age and genetics — may benefit from the habit, Fiala said, referencing a 2023 study which found night owls tend to rely on their snooze button more.
'If your chronotype is nocturnal, you're a night owl, but your work schedule requires you to be up at 5 a.m., that increases the dissonance between what your body is naturally inclined to do,' Fiala said.
For these night owls, the brief period of light sleep induced by the snooze button may actually help them transition from deeper stages of sleep interrupted by the first alarm into wakefulness, he said, adding that more research should be done to fully understand this effect and its limitations.
Regardless of one's chronotype, this distinction of who gets the most out of snoozing can also help inform how to get the most out of snoozing.
Most sleep experts emphasize adults get the recommended 7 to 9 hours of sleep per night for good health and emotional well-being. Sleeping enough can also reduce feelings of tiredness upon waking, but the consistency of your sleep timing is just as important as duration, said Kimberly Honn, an associate professor of psychology at Washington State University Spokane.
At deep stages of sleep, electric pulses of the brain reach a highly rhythmic pattern different from our more erratic, awakened state, she explained. Trying to wake up during these stages cuts important brain maintenance processes short and can lead one to experience the foggy effects of sleep inertia, which can last for several minutes or even hours after waking up.
When the body is accustomed to a regular sleep schedule, it may reduce the experience of sleep inertia upon waking, Honn said. The body can grow accustomed to moving through each sleep stage at similar times, ensuring sleep cycles are completed before waking and eventually allowing you to fall asleep faster.
'In the perfect world, we would not be relying on an alarm clock at all,' Robbins said. 'We would be able to fall asleep and wake up naturally and have energy throughout the day.'
Fiala said he generally recommends varying bedtimes by no more than 30 minutes per night, even on weekends. If you have to switch schedules, he says you should change it incrementally over time.
It's possible people who use the snooze button less simply don't have the luxury to sleep past their alarm, Robbins suggested.
Inflexible work schedules could require first responders to start their shift promptly, or parents may have to rally their children out the door and toward the school bus.
For this reason, Robbins recommends those trying to ditch a snoozing habit introduce more time constraints into their morning routine by setting the first alarm as late as possible.
'Ask yourself: Is there anything in that morning routine that you could maybe do without? Or maybe you could find a way to do it faster?' Robbins said.
Snoozing could also mean you're losing out on time that could be used for adding wakefulness-promoting habits into your morning routine.
The heaviest snoozers tracked in Robbins' study used around 22 to 27 minutes resting after the first alarm — time that could be used for stretching, journaling or cooking a nutritious breakfast, Robbins suggested.
'We talk a lot about wind down routines and bedtime rituals. I think morning rituals are also really lovely to help you get excited about your day,' Robbins said. 'It's important to find something to look forward to, whether that's a meeting in the morning, making yourself a cup of coffee, whatever helps motivate you (and) gets you out of bed.'
Timing your alarm to the sunrise and allowing natural light to come through your windows in the morning can also help signal your body to wake up, Honn said.