Sleep to Recover: How to improve your health through sleep quality & depth

Sleep & Recovery

We learn early in life how important sleep is for our development and functionality. It is evident in how our sleep is prioritized throughout our childhood. As we grow older and life speeds up, we seem to forget this fact and start neglecting sleep, even labeling it with negative connotations, usually laziness. But sleep is anything but a lazy activity. In fact, it is crucial for hormone balance, brain and body healing. 

In this post, we will dive into how to improve your health through sleep quality by understanding:

  • why prioritizing sleep is important
  • what effect sleep has on our health
  • why the quality of our sleep is as important as getting the recommended hours of sleep
  • what actions you can take to improve your sleep quality

Overnight therapy: Why sleep is so important

It’s a myth that as we grow older, we need less sleep. We, in fact, need as much sleep in our 60s as we do in our 20s because recovery is essential whether you are young or old. To quote the sleep expert, Professor Matthew Walker, director of the Center for Human Sleep Science at UC Berkley, “sleep is probably the single most effective thing you can do to reset your body and health.” 

Let’s examine exactly why that is.

Sleep contributes to our emotional well-being as it functions as a therapy to help us fight off feelings of depression and anxiety. Furthermore, it enhances cognitive performance, boosts our immune system, increases longevity, has an anti-aging effect – and even makes us look more attractive! 

That’s not all: We even get smarter when waking up from a good night’s sleep. You probably heard somebody say, “Tomorrow will look different. Sleep on the problem,” well it might be one of the best pieces of advice you can get. Sleep enhances our memories and creativity as our brain processes new information, ties it with stored memories, and identifies new patterns – helping us find solutions we couldn’t make out before.

How does poor sleep affect your health, hormones, and weight? 

To further emphasize the importance of sleep, let’s talk about what can happen if you are underslept.

It can play out as emotional instability the next day. We might become irrational, impulsive or suddenly need to seek out sensations and rewards. This is because the prefrontal cortex – the logical part of our brain – takes the hit and can no longer properly regulate the part of the brain that stabilizes emotions – the amygdala.

There are also potential chronic effects since sleep functions as a “save button” for our brain when memorizing new information. Lack of sleep actually reduces our brain’s ability to lay down new memory traces by 40%. Studies show that sleep deprivation is the most significant lifestyle factor determining if you will develop Alzheimer’s disease. 

Poor sleeping habits also disturb the regulation of hormones in our bodies.

Another chain reaction deriving from lack of sleep is the one affecting our hormones. Sleep deprivation is linked to hormonal changes affecting our body’s glucose (blood sugar) regulation. Normally, when our bodies sense a spike in glucose, they start to release insulin to regulate it. If we are under-slept, our bodies (our pancreases) may become insulin insensitive and not release the adequate amount of insulin needed to regulate the glucose spikes. This, of course, affects our glucose tolerance, which may lead to an increased risk for diabetes. In fact, people who sleep 5 hours or less per night have a significantly higher risk of being diagnosed with diabetes compared to those who sleep 8 hours. 

If you plan to start on that healthy diet, make sure to plan for good sleep too! Studies show that sleep deprivation affects the hormones that regulate our hunger. Lack of sleep causes an increase in certain hormones that stimulate hunger and a decrease in other hormones that let us know when we are full. This means that if you are sleep deprived, you will most likely crave and eat more food than you actually need, especially food rich in fats and carbs. This, in turn, is an entry ticket for a glucose roller coaster. 

Does the number of sleeping hours matter?

It definitely does, but remember that quantity and quality are equally important here.

The recommended hours of sleep are between 7-9 hours, with 8 hours being the ideal for most people.

But how do I know if 8 hours of sleep is enough for me? Well, let’s say your alarm didn’t go off one morning. Would you continue to sleep? If yes, you are not getting enough sleep. 

Sleeping stages and why they matter?

Before we take steps to improve our sleep quality, it helps to understand the four stages of sleep: there are three NREM (non-rapid-eye movement) stages and one REM (rapid-eye movement) stage.

Stage 1. The “dozing off” stage occurs right before you fall asleep.

Stage 2. During this stage, your heart rate, brain activity, and body temperature are lower. 

Stage 3. Here is where we enter deep sleep or slow-wave sleep (SWS). This stage is considered critical for restorative sleep and essential for your body’s glucose management. 

Stage 4. In the crucial REM stage, brain activity picks up rapidly. It is restorative to cognitive functions such as creativity, learning and memory.

The stages move in a cycling pattern and have varying lengths. The length of each stage can be influenced, and this is how our lifestyle choices come into play.

Pulling all-nighters, having an irregular sleep schedule or regularly having your sleep disturbed are all factors that can negatively affect the sleep stages and in turn, affect your physical and mental recovery.

Therefore, sleep quality means optimizing the different sleeping stages, especially deep sleep (SWS) and REM.  

To assess your sleep quality, ask yourself these questions: 

  • Does it take you more than 30 min to fall asleep? 
  • Do you wake up several times per night and have trouble going back to sleep?
  • Do you feel tired and have difficulty talking and concentrating the next day?
  • Do you feel more hungry, experience cravings, and feel emotionally less stable?

If one or more of these apply to you, we have some remedies you may want to try.

How to improve sleep with lifestyle choices


The Circadian Rhythm

Almost all living beings – from bacteria to people – have a circadian rhythm. It is our “internal clock” that ensures that all of our organs and internal biological systems work harmoniously together over a 24h cycle. One of the most important processes, controlled by the circadian rhythm, is the sleep-wake cycle. It is regulated through a complex feedback loop that includes hormonal production (most prominently melatonin) interlinked among others to light exposure and sleeping patterns.

  • Always wake up at the same time: Abandon those plans to catch up on sleep during the weekends. Our bodies love routines, so try to follow a steady sleep- and wake-up schedule. This is best kept in check by always waking up at the same time, whether it is the weekend or even if you went out partying the night before. By waking up at the same time, your body will take the sleep it needs by “making you” go to bed earlier the next day! This will help foster a healthy circadian rhythm and teach your body to follow a specific sleep-wake cycle which can help you fall asleep quicker and improve your sleep quality.
  • Create a bedtime ritual to unwind: Relaxation before bedtime signals that it’s time for your body and brain to unwind. So, dim those lights, put on calming music, take a warm bath, get your favorite book or do whatever it is that makes you relax. Your circadian clock responds the best if you start to dim the lights in your home 3-4 hours before your bedtime. The darkness kicks off melatonin production, which causes drowsiness and helps initiate the sleep phase. Blue light is our main adversary here, that’s why most phones and laptops have a downtime mode, where you can set up times when the blue light is automatically reduced. But ideally, you would avoid screens altogether during your wind-down phase. 
  • Your morning ritual matters, too: Light exposure works both ways – within 30 minutes of waking up, go outside and expose your eyes to sunlight for 2-10 minutes. This triggers a healthy cortisol release to promote wakefulness and starts the timer for melatonin. Meaning, if you get bright light exposure 14-16 hours before when you want to sleep, it will help to time the melatonin release exactly when it is time for you to start getting ready for sleep. It doesn’t matter if it is winter or cloudy, just don’t wear sunglasses.
  • Avoid a glucose spike late in the evening: Avoid eating heavy meals or snacking late in the evening. It can cause indigestion and high glucose levels, which directly disrupts your deep sleep. 
  • Manage your glucose levels: Find out through glucose monitoring which foods give you spikes and lows in glucose. An interesting fact is that the circadian rhythm regulates your glucose metabolism. Therefore, a circadian disruption, such as ending a night out with a pizza or other “heavy” food, can cause glucose dysregulation.


Interesting Fact

Did you know that our liver works hardest when we are in the middle of our sleep? As elaborated above, our body “knows” due to the circadian rhythm when we are deep in sleep and that’s when some parts of our body work hardest. It is during this time (usually 1am – 4am) that we experience the most glucose dips and spikes. This is because our liver works hardest during this period to detoxify our body causing the erratic glucose levels.

  • Temperature: A cooler bedroom temperature is perfect for sleep as your body needs to drop 1-3 degrees for effective sleep.
  • Avoid alcohol: While a glass of good wine for dinner or some fun cocktails when out with your friends is part of life, it’s important to understand that alcohol will definitely mess with your sleep. Alcohol is technically a sedative that can aid in falling asleep, but in reality, it basically knocks you out. To put it bluntly: you’re not falling asleep, you’re passing out. This means it reduces the deep SWS and REM sleep and causes sleep disruption throughout the night, consequently messing with your sleep quality and recovery.
  • Exercise: Working out is a cure for all, including poor sleep and unstable glucose levels. But you should avoid heavy exercises that drive up your heart rate late in the evening. This goes especially for high-intensity training like HIIT, heavy weight lifting, or even a late evening jog. Instead, opt for low heartbeat activities like easy Yoga or Qi Gong.
  • Caffeine is all about timing: Would you drink one espresso as a good nightcap? No, right? But drinking 2 espressi at 5 pm, is like having 1 espresso at 10 pm. This is because caffeine has a half-life of 4-6 hours, meaning it takes your body that long to get rid of half the amount of the consumed caffeine. Caffeine is a stimulant and will keep you awake while it is in your system in a higher amount. Even if you manage to fall asleep with caffeine in your system, it will disrupt the SWS stage and lead to less restorative sleep. So, make sure to time your coffee or matcha well. 

The key takeaways:

Sleeping is crucial for your body’s physiological and mental recovery. The severe consequences of not prioritizing sleep include diseases, functional impairments, and elevated glucose levels.

You should aim to get 7-9 hours of sleep and work to enhance SWS (stage 3) and REM sleep (stage 4). 

Therefore, you should really analyze which daily choices in your life might affect your sleep quality. So heal your circadian rhythm: if your circadian clock is off, it can cause you sleep problems. Boost it by following a sleeping schedule, avoiding staying up at night, and avoiding eating in the evenings. 

One particularly important factor is stable glucose levels, which impact your hormones, your sleep quality, and, therefore, your recovery. Understanding how your body reacts to glucose levels helps you make healthy lifestyle choices. Hello Inside has designed a program that helps you understand your body’s response to food, exercise, and sleep. 

Hello Hormones is the name, and it includes personalized practical insights to help you make smarter lifestyle choices to enhance every aspect of your life, including sleep. 


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Aulona Krasniqi

Aulona Krasniqi

Aulona Krasniqi is a contributing writer for Hello Inside. She holds a Master of Science in International Health from Charite Medical University in Berlin, Germany. Her passion lies in promoting quality food and healthy lifestyles to the broader public.

more posts from author
Aulona Krasniqi

Aulona Krasniqi

Aulona Krasniqi is a contributing writer for Hello Inside. She holds a Master of Science in International Health from Charite Medical University in Berlin, Germany. Her passion lies in promoting quality food and healthy lifestyles to the broader public.

more posts from author

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