Sleep is an essential part of our daily routine. It’s as necessary as food and water. Without sleep, we wouldn’t be able to maintain or form neural networks to allow the assimilation of new information while also hindering the process of concentration and rapid response in certain situations.
Sleep is vital for many brain functions, including how neurons communicate with each other. In fact, the brain and the body, in general, remain very active during sleep. Recent research suggests that sleep plays an essential role in eliminating toxins from the brain that accumulate daily. It also affects almost every type of tissue and system in the body, from the brain, heart, and lungs, to metabolism, the immune system, mood, and disease resistance.
The most common causes of difficulty falling asleep or maintaining sleep are living at the daily maximum intensity stress levels, a disorganized lifestyle, and no sleep ritual.
Let’s see how to go into a deep sleep and what you should do to get more deep sleep.
What is deep sleep and why is it important?
Deep, or slow-wave, sleep is a type of non-REM (non-rapid eye movement) sleep and is associated with the slowest brain waves while sleeping. It’s an essential part of the sleep cycle that helps the brain and memory function. A few reasons why a night of deep and restful sleep is so important is because, in those moments, the immune system is stimulated, toxins are cleared from the cerebrospinal fluid, and the body secretes growth hormones, which are necessary for the regeneration of tissues, bones, and muscles. Usually, adults need 7 – 9 hours of sleep per night, spending about 15% - 20% of that time in a deep sleep.
What are the stages of sleep?
While we sleep, we usually go through three phases: stages 1, 2, 3, to which REM sleep, characterized by rapid eye movement, is added. The first three stages are called non-REM sleep (NREM).
The progressive passage through these stages of sleep, from stage 1 to REM, forms a continuous sleep cycle. A complete sleep cycle in adults lasts between 90 and 110 minutes.
Non-REM Sleep - Stage 1
At this stage, sleeping is smooth. We pass from a waking state to a sleeping state, and we can easily be awakened by the slightest noise. Our eyes move very slowly, and muscle activity slows down. We also experience sudden, involuntary muscle contractions called myoclonus, often preceded by a feeling of falling into emptiness. People awakened from this stage often remember fragmented visual images.
Non-REM Sleep - Stage 2
When we enter this second stage of sleep, eye movement stops, the heart begins to beat more slowly, the muscles relax, and body temperature drops. Also, brain waves (fluctuations in electrical activity, which can be measured by electrodes) slow down, and a series of occasional fast waves called sleep spindles appear. Basically, it's your body preparing for deep sleep. This part of the cycle takes about 20 minutes and, according to the American Sleep Foundation, people spend about 50% of their total sleep at this stage.
Non-REM Sleep – Stage 3
During stage 3 of sleep, the muscles relax further, and blood pressure and respiratory rate decreases. At this stage, the deepest and most valuable part of sleep takes place. The reason is that, at this stage, the body and brain recover the most with the brain strengthening factual memories. Growth hormones are also released at this time.
During REM sleep, the brain is more active, while our body is relaxed and immobile. This is the moment when dreams appear, and our eyes move fast underneath our eyelids. REM sleep is characterized by eye movement, increased respiratory rate, and increased brain activity. The American Sleep Foundation shows that people spend about 20% of their total sleep at this stage.
In this stage, the brain learns how to use factual memories and creates links between information and how to implement it. In other words, this is the time to solve problems!
On average, we enter the REM stage about 90 minutes after falling asleep. While the first REM sleep cycle can last only a short time, it lasts longer with each cycle. REM sleep can last up to an hour as sleep progresses.
What are the benefits of deep sleep?
As mentioned at the beginning of the article, the body releases growth hormones important for tissue development and repair during deep sleep. But deep sleep can also play an essential role in eliminating metabolic waste from the brain through the lymphatic system. This improves memory processing and consolidation, optimizes immune system function, and restores cellular energy stores.
Other benefits of deep sleep include:
- Maintaining a healthy weight.
- Decreasing the risk of heart disease.
- Preventing diabetes.
- Stimulating fertility.
What happens when you don’t get enough deep sleep?
During deep sleep, glucose metabolism in the brain increases, supporting short-term memory, long-term memory, and overall learning. Not getting enough deep sleep can lead to health conditions like:
- Dementia and Alzheimer’s disease.
- High blood pressure.
- Heart attack.
- Type 2 diabetes.
How much deep sleep do you need?
According to the Institute of Medicine, people spend between 75% – 80% of their night in non-REM sleep, about 20% - 25% in REM sleep, and around 13 - 23% in a deep sleep.
While newborns and babies need 2.4 to 3.6 hours of deep sleep, teenagers need around 1.7 to 2 hours of deep sleep, the elderly and those over 65 may get only half an hour of deep sleep.
There are no specific requirements for deep sleep. However, one explanation for why young people may need more deep sleep is because they’re in the process of growing and developing.
How to get better REM sleep?
1. Put the phone aside.
Many of us are addicted to our cell phones, which we use from the time we open our eyes in the morning until late in the evening, going so far as to even falling asleep with the phone in our hands. The blue light emitted from our mobile phone, tablet, or digital clock can affect deep sleep.
Specialists at the Mayo Clinic recommend avoiding the use of these devices at least one hour before bedtime. So put the phone and tablet aside, and cover the watch with a handkerchief. Also, avoid watching TV or working on your laptop when you go to bed. Indeed, it’s difficult to stay away from the laptop, but you’ll find that it is worth the effort for a restful sleep.
2. Develop a sleep schedule.
It may seem a little strange that a well-crafted program is needed to regulate sleep, especially since you are stuck with all sorts of deadlines and schedules during the day, but this is what specialists advise.
Thus, go to bed every night at the same time for three weeks, without exception (including Saturday and Sunday), and get out of bed in the morning at the same time every day. If you fail, especially on weekends, try to limit the difference between bedtime and waking hours during the week and the weekend to a maximum of one hour. This is the only way to strengthen your body's sleep-wake cycle.
There is a risk that you will not be able to stick to such a program every day because the amount of fatigue accumulated during the day will also matter a lot. However, if you don’t fall asleep in about 20 minutes from the moment you sit in bed, do not stress. Instead find something soothing to do like reading or listening to soft music. Return to bed only when you feel acute fatigue.
3. Atmosphere can make a difference.
The atmosphere you create in the bedroom influences your deep sleep. You need a relaxing environment to convey to the brain that it’s time to get rid of the day's stress. The bedroom should be dark, with a slightly lower temperature than the rest of the house, and no noise sources.
For a good night's sleep, the room temperature should be between 60 and 68°F. Make sure it's quiet. Eliminate various sources of noise that may wake you up during the night. You can confidently use black out curtains, eye masks, earplugs, and "white noise" devices that play songs or relaxing sounds.
4. Avoid cigarettes, and heavy meals during the evening.
Alcohol, cigarettes, and caffeine disrupt sleep. Fatty or spicy foods can irritate the gut and keep you awake longer. It’s recommended to avoid any food at least 2 hours before bedtime.
5. Create a relaxing bedtime routine.
A relaxing activity just before bed, in low light, can help you make the transition from the demanding activities of the day to the peace you need to fall asleep.
6. Exercise regularly.
Regular physical activity can help you sleep better and get more deep sleep. You can do intense workouts during the day but not before bed, because it can increase body temperature, increase heart activity and stimulate adrenaline production. After a certain hour, it may compromise your sleep. It’s recommended that at least two hours pass between training and bedtime because otherwise, your adrenaline level will be high, your brain active, and the state of relaxation needed to fall asleep easily will be more difficult.
7. Choose the right pillows.
Try to use a comfortable pillow, adapted to your sleeping style (on the back, on one side, etc.), and if you are allergic to dust, choose an anti-allergy pillow.
8. Try sleeping supplements meant to relax you
A natural, organic formula meant to relax you can do wonders for your sleep. Try the Elderberry Hill Nighttime Formula, taken an hour before going to sleep, and feel how it washes the stress of the day away. It’s rich in vitamins and minerals that will help you relax and unwind, so you can sleep better and deeper.
How do you know how much deep sleep you’re getting?
If you wake up exhausted, experience anxiety, have frequent episodes of waking up during the night, sleepiness during the day despite having rested, or headaches, it could be a sign that you’re not getting enough deep sleep.
Polysomnography (PSG) is a test your doctor may recommend and is done when you’re completely asleep. It measures:
- Brain waves
- Skeletal muscle activity
- Blood oxygen levels
- Heart rate
- Breathing rate
- Eye movement
Polysomnography will help your doctor chart your sleep cycles and diagnose sleep disorders, such as:
- Chronic insomnia – difficulty falling asleep or remaining asleep.
- REM sleep behavior – acting out dreams while sleeping.
- Narcolepsy – abnormal sleep and daytime drowsiness.
Deep sleep plays a crucial role in cognitive functioning, contributing to memory consolidation, brain restoration, and cell regeneration. Sometimes, going to sleep early doesn’t mean you’ll also get enough deep sleep. Apart from this, a healthy diet, regular exercise, and practicing mindfulness to get rid of daily stress will also help you increase your slow-wave sleep.
What methods do you know about how to get into a deep sleep? We are curious to find out.