Every single night, we go through multiple sleep cycles comprised of different sleep stages. These stages are divided into non-REM (non-rapid eye movement) stages and a REM stage. While there are many questions we have yet to uncover regarding our sleep cycles, we do know at exactly which stage deep sleep occurs. If you’ve ever wondered how long does it take to go into deep sleep, you’ve come to the right place.
In this article, we will cover exactly what deep sleep is, what some of its benefits are, the processes that occur during each sleep stage, and give you some tips on how to get more deep sleep every night.
With all that out of the way, let’s define what deep sleep is.
What Is Deep Sleep?
Deep sleep happens during the third stage of the sleep cycle and it’s part of the non-REM stages. During this stage, the waves in our brain, also referred to as delta waves, are at their slowest, which is why deep sleep is sometimes referred to as slow-wave sleep.
We enter deep sleep multiple times during the night, approximately one hour after we initially fall asleep. It’s interesting to note that the period of deep sleep tends to get shorter as the night passes. The more sleep cycles we go through during the night, the longer time we spend in REM sleep (the fourth and final stage of sleep), which leaves less time for the other stages.
But, before deep sleep actually occurs, there are two other stages we have to go through first.
The first stage of non-REM sleep is the shortest in duration and it usually lasts anywhere from one to five minutes. This is when we’re most prone to being woken up since we’re at an in-between stage of being conscious and asleep. Some other changes occur in the body and brain, such as the brain waves starting to slow down.
Other changes that occur in the body during this stage include our heartbeat slowing down and a slight drop in temperature. If we manage to get past this initial stage of the sleep cycle, we successfully move on to the second stage.
The second stage of non-REM sleep usually lasts from 10 to 25 minutes. Our brain waves continuously slow down, but there are sudden spikes in the brain waves. These spikes have a special purpose – they prevent us from being woken up by any noise we might hear in the room, or by any sudden exposure to light.
The changes in our bodies continue; our temperature drops, the muscles in our body become more relaxed, and our heart rate becomes even slower. Apart from the rapid spikes in brain waves, a couple of other interesting phenomena happen in our brain. For instance, it’s during this stage that our brain starts shifting through some of the memories we’ve made throughout the day.
Deep sleep happens during the third stage of the sleep cycle, the last stage of the non-REM group.
This stage is crucial for many important processes in our body, such as muscle building, maintaining a healthy immune system, and cell regeneration. Deep sleep also plays a vital role in the formation of our long-term memories.
It’s not easy to be woken up by someone during this stage, but if you do manage to wake up during deep sleep, it won’t be a fun ride. People who are suddenly woken up during the third stage of sleep usually wake up groggy, confused, and in a bad mood. If you find yourself waking up in this state constantly, you might want to try downloading an app that tracks your sleep cycle and wakes you up at the end of the fourth and final stage.
The third stage can last anywhere from 20 to 40 minutes at a time. We enter deep sleep multiple times during the night, but how much deep sleep we get per night depends on the sleep cycle.
While the processes in our bodies slow down during the first three stages of a sleep cycle, the last stage of sleep, also known as REM sleep, is characterized by an increase in our heart rate, breathing, and blood pressure. Just like its name suggests, during this stage, our eye movements also speed up.
Even though we can dream during the other stages of the sleep cycle, most of our dreams occur during the REM stage of sleep. In terms of duration, it can last anywhere from a couple of minutes during the first sleep cycle of the night, to twenty, even up to thirty minutes during the last sleep cycle. Overall, REM sleep accounts for approximately 25% of our total sleep.
The Benefits of Deep Sleep
Every stage of the sleep cycle occurs for a reason and every stage contributes to our overall health and the vital processes in our bodies. Here are some of the benefits of deep sleep that are unique to this stage.
It’s during the third stage of sleep that the process of muscle repair transpires. The tears we make in our muscles while lifting heavy objects or working out are rebuilt during this stage because our body releases a significant amount of growth hormone. If you’re someone who often goes to the gym, this is one of the reasons why you should prioritise sleep and treat it just as seriously as you do your diet.
Deep sleep also contributes to healthy cognitive abilities, such as memory processing, language learning, and problem-solving.
We all know that getting enough sleep is crucial for a healthy metabolism and weight. According to this study, deep sleep also helps with managing blood sugar and avoiding sugar spikes, which is important for our overall health.
Additionally, deep sleep is also when the body strengthens the immune system and repairs itself.
Do Sleep Disorders Occur During Deep Sleep?
It’s interesting to note that there are many sleep disorders which occur specifically during deep sleep. Some of these disorders include sleepwalking, sleep eating, and nightmares. Being in deep sleep explains why sleepwalkers don’t remember their sleepwalking episodes. However, that’s also what makes them quite dangerous – sleepwalkers aren’t aware of their surroundings and they can very easily injure themselves during one of these episodes.
How Much Deep Sleep Do You Need?
How much deep sleep you need every night depends on your age. Infants and children spend a large percentage of their night in deep sleep. As you get older, this percentage goes down. If the average adult spends around two hours in deep sleep per night, whereas an elderly person would get less than an hour.
There isn’t a set number of hours you should spend in deep sleep every night, but young people and athletes require it more due to the growth hormone release and general rejuvenating benefits.
Now that you know the benefits of deep sleep, let’s go over some of the drawbacks you might experience if you struggle to get enough deep sleep every night.
The Possible Consequences of Not Getting Enough Deep Sleep
There are some universal tell-tale signs you should watch out for. You might notice that you’re experiencing brain fog or that your memory is impaired. You will have trouble concentrating and staying alert for a longer period of time.
If you’ve gone through a longer period of not getting enough sleep, your immune system might suffer and you might catch yourself getting frequent colds.
Sleep is crucial for regulating our emotions, so you also might struggle with mood swings and chronic grogginess.
In addition, when we’re sleep deprived, our bodies naturally gravitate towards higher calorie food and our appetite is increased.
Getting too little deep sleep on a regular basis is linked to some serious health conditions, like heart disease and dementia, so if you suspect that you’re not getting enough deep sleep, you might want to consult your doctor.
Tips for Getting Enough Deep Sleep
As you can see, our health is at serious risk when we struggle to get enough sleep. To help you improve your sleep pattern and increase the amount of deep sleep you’re getting, we’ve included some of our top tips.
Exercising on a regular basis is one of the healthiest habits we could foster. Unless you’re doing it right before bed, which can cause you to stay up, regular exercise has been linked to an improved sleeping pattern. Tiring your body out in a good way will make it easier for you to fall asleep at night, so it’s worth considering if you’ve been struggling with regular sleep.
Pay Attention to What You Consume
Improving your diet doesn’t only include eating enough vegetables and drinking enough water, but it also includes avoiding certain foods and drinks that could be detrimental to your sleep. Consuming large quantities of alcohol or caffeine before bed will make you more prone to waking up in the middle of the night, thus interrupting your sleep cycles. If you’re a fan of coffee or the occasional glass of wine, make sure you consume your last drink at least a couple of hours before bed.
Optimise Your Sleeping Environment
Making certain changes in your sleeping environment, such as turning off the lights, putting on a relaxing playlist or white noise, or lowering the temperature of your room can significantly improve your overall sleep and help you avoid wasting hours tossing and turning in your bed, unable to fall asleep.
Can You Get Too Much Deep Sleep?
Getting more than nine hours of sleep can be just as harmful as being sleep deprived and it can increase your risk of diabetes and heart disease, so make sure you stick to seven to eight hours.
How to Get More Deep Sleep?
Limiting your alcohol and caffeine intake, exercising regularly, and downloading a sleep cycle tracking app can help you get more deep sleep.
We enter deep sleep during the third stage of our sleep cycle, approximately one hour after we fall asleep. Many important processes in our body occur during this sleeping stage, such as muscle building, memory retention, and cell repair. Deep sleep is crucial for our overall health and not getting enough deep sleep every night can result in many side effects, such as an impaired immune system, trouble concentrating and problem-solving, mood swings, and an increased risk of certain diseases like dementia and heart disease.
Luckily, there are plenty of ways we can encourage our bodies to get enough deep sleep. We recommend getting enough exercise every day, optimizing your sleeping environment, installing a sleep cycle tracking app, and limiting your alcohol and caffeine intake in the evenings.
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