Hitting the snooze button on your alarm clock might be totally fine, new research shows this week. In two studies, scientists found evidence that the majority of people nap regularly and that this habit doesn’t appear to noticeably affect our sleep. It might even help some people feel more awake in the morning.
The research was conducted by scientists from Sweden and Australia led by Tina Sundelin, a psychologist and sleep researcher at Stockholm University. Sundelin was at times an avid slumber. And like many people, she had long heard about the supposed negative effects of sleeping on health. But when Sundelin looked closer, she couldn’t find any real data to support this claim.
“As a sleep researcher, I tried to find the evidence for this but couldn’t find a single study,” she told Gizmodo in an email.
To better understand sleep, she and her colleagues decided to conduct two studies. In the first step, they surveyed over 1,700 people online about their sleeping habits. 69% of respondents said they used the snooze button on their alarm clock or set multiple alarm clocks at least some of the time. People who snoozed were generally younger than non-snoozers and were more likely to be night owls. They also reported that they slept slightly less on weekdays (about 13 minutes less) and that they were sleepy more often in the morning. Importantly, however, there was no significant difference in the average sleep quality of both groups.
“The most common reason for snoozing is feeling too tired to wake up, but many also sleep because it feels good,” Sundelin noted.
In the second study, the team recruited 31 self-identified habitual sleepers to be closely monitored in a sleep laboratory for three non-consecutive nights. After the first night of normal sleep, each participant slept one night in which they were allowed to snooze and the other in which they were not allowed to snooze. The following day, volunteers performed simple cognitive tests in the morning and afternoon.
The researchers found no significant difference in people’s stress hormone levels, morning sleepiness, mood, and overall sleep structure, regardless of whether they dozed or not. People lost about six minutes of sleep when they dozed, but they were also less likely to wake up from deep sleep, which can make our sleep quality worse Sleep inertia– the temporary lightheadedness we feel when we wake up. And on average, people actually performed slightly better on several cognitive tests in the morning when they were asleep, suggesting that it made them more alert.
The work of the team, published Wednesday in the Journal of Sleep Research is one of the first to examine the effects of sleep. But their results are generally consistent with another study published last year, which found that sleepers did not sleep significantly less and, on average, did not feel sleepier than non-sleepers. So at least it doesn’t seem to be harmful for people who fall asleep regularly. And it could even be an adaptive behavior for people who like to sleep longer at night or need more time in the morning to reduce their sleep inertia, the authors theorize.
“I wouldn’t recommend that those who don’t sleep start sleeping, but for those who find sleeping helpful (or luxurious), there’s no reason to stop as long as it’s not excessive and you get the necessary amount from it, get the sleep you need (and maybe as long as you don’t disturb the sleep of those around you!),” Sundelin said.
Future studies on sleep should ideally examine larger samples or attempt to track the long-term effects of sleep, she added. She and her team are already researching other ways people’s sleep can be disrupted and how this can affect their waking behavior. They are currently studying the effects of sleep inertia in physicians who sleep while on call.