People who hit the snooze button on their alarm may feel less groggy and experience better cognitive performance after waking than those who get up as soon as the alarm clock goes off.
Getting up and out of bed in the morning can be difficult for some people — especially those who aren't morning people — and setting multiple alarms or repeatedly hitting the snooze button is a common way to deal with those challenges. Reasons for snoozing can vary, but feeling tired upon waking and sleep conditions like paradoxical insomnia or sleep apnea may play a role in sleep quality.
However, can hitting snooze negatively impact how a person feels and functions throughout the day?
In research conducted at Stockholm University in Sweden, scientists aimed to answer that question by examining the characteristics of snooze time and investigating its potential effects on mood, cognitive function, and sleepiness. The study results were published on October 17 in the Journal of Sleep Research.
In the first part of the study, 1,732 participants, with an average age of 34 years, responded to survey questions asking about their snooze behavior.
In all, 69% of the participants reported at least sometimes hitting snooze buttons on their alarm clocks or setting multiple alarms. Among those who snoozed, 60% said they most often or always fell back to sleep between the alarms. Moreover, these participants spent an average of 22 minutes snoozing per morning, with alarm intervals averaging eight minutes.
Individuals who engaged in snoozing behavior were around six years younger and four times more likely to be an evening person than those who didn't hit the snooze button.
Compared to people who never hit snooze, those who snoozed experienced about 13 minutes less sleep on workdays and were more likely to feel drowsy upon waking.
Moreover, 25% of the snoozing participants said they engaged in this behavior because they felt too tired to wake up.
Does hitting the snooze button do more harm than good?
In the second part of the study, the sleep scientists measured the effects of snoozing and not snoozing on sleepiness, sleep architecture, cognitive ability, and mood in 31 participants.
During the snooze and no snooze periods, the participants provided a saliva sample upon waking. They also underwent cognitive testing using the Karolinska WakeApp, which involved four cognitive tests to assess processing speed, episodic memory, and executive functioning. In addition, the participants rated their mood, sleepiness, and performance after each cognitive test. Then, they repeated these assessments 40 minutes later.
The research team found that while both snooze and no snooze participants felt groggy upon waking, those who slept in for 30 minutes performed better on three out of the four cognitive tests compared to individuals who got up when the initial alarm went off.
Moreover, snoozing had little impact on stress hormone levels, morning routine sleepiness, mood, or overnight sleep structure.
The scientists report that participants who snoozed lost about six minutes of sleep, but hitting snooze prevented awakening from deep sleep, which can cause grogginess.
"Regular snoozers tend to feel more mentally drowsy upon waking, which goes along with the finding that they are younger and later chronotypes than those who never snooze," the study's authors wrote. "These individuals may need more time to ward off the effects of sleep inertia, and snoozing may be a potential way of doing this."
However, the scientists suggest snoozing for 30 minutes might not benefit people who don't get the recommended seven or more hours of sleep or experience disrupted sleep, which results in sleep deprivation. In addition, though snoozing only had a small impact on the stages of sleep, it slightly increased the participants' sleepiness and effort required later in the day, and these adverse effects could accumulate over time.