Scientists reveal why you should NEVER hit the snooze button - as research reveals over half of us are guilty of reaching for it
- READ MORE: Experts reveal what six hours of sleep a night will do to your body
When the dreaded morning alarm goes off, it's always tempting to reach for the snooze button.
But according to scientists, hitting snooze may not help your body get the restorative sleep you need.
Researchers at Brigham and Women's Hospital in Massachusetts reveal that pressing the snooze function on an alarm clock is a common practice.
Even though it isn't recommended by sleep experts, more than half of us opt to snooze on average, they say.
Overall, we spend an average of 11 minutes in between snooze alarms each morning before waking.
However, snooze alarms disrupt key sleep stages and can make it harder to feel refreshed during the day.
'Many of us hit the snooze alarm in the morning with the hope of getting a little more sleep,' said study author Dr Rebecca Robbins.
'But this widely practiced phenomenon has received little attention in sleep research.'
It's a common habit, but here's why you shouldn't hit the snooze button, according to sleep experts (file photo)
According to Dr Robbins, the hours just before first waking up are rich in rapid eye movement sleep (REM), possibly the most crucial sleep stage.
REM sleep, described as a restorative sleep state, is particularly important because it plays a role in memory consolidation, cognitive functioning and emotional processing.
However, when we go back to sleep after hitting snooze on the alarm, the snooze stage typically only offers light sleep, not REM sleep.
So, according to the experts, we might as well make our initial alarm later so we can get more REM sleep – rather than interrupt it with the snooze alarm.
In other words, if we can sleep later anyway, we might as well just skip the snooze alarm altogether.
'The best approach for optimizing your sleep and next day performance is to set your alarm for the latest possible time, then commit to getting out of bed when your first alarm goes off,' Dr Robbins said.
For their study, Dr Robbins and colleagues analyzed sleep data from more than 21,000 people globally using data from the sleep tracking smartphone app Sleep Cycle.
The study represented six months of data and more than 3 million sleep sessions from users across four continents.
This image from the paper plots sleep and snooze alarm behaviour of 500 users selected at random in the month of October, sorted from least snooze alarm use (green) to most snooze alarm use (red). White indicates no sleep session is logged
On the nights that participants logged a sleep session, more than half (55.6 per cent) of the sessions ended with a snooze alarm.
Overall, users spent an average of 11 minutes in between snooze alarms each morning before waking and going about their day.
But 45 per cent of study subjects hit the snooze button on more than 80 per cent of mornings – described as 'heavy users' who snoozed, on average, 20 minutes a day.
As expected, there were more snooze alarms generally during the typical working week, Monday through to Friday.
And the lowest snooze alarm use was on Saturday and Sunday mornings as people were usually able to enjoy an alarm-free lie-in.
The team also found that long sleep sessions (more than nine hours) were more likely to end with snooze alarm use than nine hours or less.
Sleepers who went to bed earlier used the snooze alarm less, while those who went to bed later used the snooze alarm more.
People in the US, Sweden and Germany had the highest snooze button use, while those living in Japan and Australia had the lowest.
The results reveal more snooze alarm Monday through Friday and less snooze alarm use on Saturday and Sunday - a finding which may be explained by fewer commitments on the weekend
Interestingly, the researchers observed significantly more snooze alarm use in women compared with men.
'It is possible the gender difference observed in snooze alarm behaviour stems from the increased risk for insomnia among women as compared to men,' the team report.
'In addition, women shoulder a greater burden of childcare duties compared to men, which may be on top of professional or other duties, therefore reducing the time available to women for sleep and increasing risk for sleep difficulties, which may increase reliance upon snooze alarm.'
The team also saw minimal month-to-month differences, although there was slightly more snooze alarm use in December and less in September for those in the Northern Hemisphere (and the opposite among those who in the Southern Hemisphere).
The study, published in Scientific Reports, finally adds to the available evidence in the scientific literature on snooze alarm use.
'Future research is needed to understand the impact of snooze alarm use on daytime performance,' the team conclude.
THE FOUR STAGES OF SLEEP
Pictured, different steps of the night sleep cycle. Most dreaming occurs during REM sleep (marked in red) although some can also occur in non-REM sleep
Sleep is generally separated in four stages. The first three of these are known as 'non rapid eye movement' or NREM sleep.
The last stage is known as rapid eye movement or REM sleep.
A typical night's sleep goes back and forth between the stages.
Stage 1: In the first five minutes or so after dropping off we are not deeply asleep.
We are still aware of our surroundings but our muscles start to relax, the heart beat slows down and brainwave patterns, known as theta waves, become irregular but rapid.
Although we are asleep during Stage 1, we may wake up from it feeling like we didn’t sleep at all.
After around five minutes our bodies move into stage two.
Stage 2: This is when we have drifted into sleep, and if awakened would know you we been asleep. Waking up is still fairly easy.
This stage is identified by short bursts of electrical activity in the brain known as spindles, and larger waves known as K-complexes, which indicate that the brain is still aware of what is going on around it before turning off to a sub-conscious level.
Heartbeat and breathing is slow, and muscles relax even further.
Our body temperature drops and eye movements stop.
Brain wave activity slows but is marked by brief bursts of electrical activity.
Stage 3: Stage 3 non-REM sleep is the period of deep sleep that we need to feel refreshed in the morning.
It occurs in longer periods during the first half of the night.
Our heartbeat and breathing slow to their lowest levels during sleep and brain waves become even slower.
Our muscles are relaxed and it people may find it difficult to awaken us.
The body repairs muscles and tissues, stimulates growth and development, boosts immune function, and builds up energy for the next day.
Hypnagogia - the transitional state between wakefulness and sleep - is associated with NREM stages one to three.
Mental phenomena during hypnagogia include lucid thought, lucid dreaming, hallucinations and sleep paralysis.
REM sleep: REM sleep first occurs about 90 minutes after falling asleep.
Our eyes move rapidly from side to side behind closed eyelids.
Mixed frequency brain wave activity becomes closer to that seen in wakefulness.
Our breathing becomes faster and irregular, and heart rate and blood pressure increase to near waking levels.
Most dreaming occurs during REM sleep, although some can also occur in non-REM sleep.
Arm and leg muscles become temporarily paralysed, which prevents us from acting out our dreams.
As we age, we spend less of our time in REM sleep.
Memory consolidation most likely requires both non-REM and REM sleep.
Source: US National Institutes of Health
