„Sleep restocks the armory of our immune system, helping prevent infection, and warding off all manner of sickness. Sleep reforms the body’s metabolic state by fine-tuning the balance of insulin and circulating glucose. Sleep further regulates our appetite, helping control body weight through healthy food selection rather than rash impulsivity. Plentiful sleep maintains a flourishing microbiome within your gut from which we know so much of our nutritional health begins. Adequate sleep is intimately tied to the fitness of our cardiovascular system, lowering blood pressure helping keep our hearts in fine condition.“Matthew Walker, Why We Sleep
…to only name some of the countless benefits of sleep. Would you have known? And there is more….
But before we dive deeper into the topic, let me spread some basic knowledge about sleep that you might want to keep in mind for later chapters and posts.
Sleep – Basics
First of all, according to the sleep foundation, an adult needs seven to nine hours of sleep every night. However, different people have different preferences about when they want to spend those seven to nine hours. And that is perfectly normal and absolutely okay. As you might have realised at some point in your life, there are people who like to get up very early in the morning because this is the time when they feel energised and concentrated as well as people who have their peak of wakefulness late in the day and therefore like to go to bed way past midnight.
Secondly, not just humans but most living creatures have what is called a circadian rhythm. Circa dian meaning around a day thus about 24 hours (but not exactly). This 24-hour-rhythm helps control „when you want to be awake and when you want to be asleep.“ But also regulates „your timed preferences for eating and drinking, your moods and emotions, the amount of urine you produce, your core body temperature, your metabolic rate, and the release of numerous hormones.“ Furthermore, our brain reacts to daylight, which is „the most reliable signal in our environment.“ Those ’signals‘ influence and are able to reset our biological clock which in return is relevant and related to sleep and sleeping patterns. To sum this up in my own words, you can influence your sleeping schedule, which is related to your biological clock, by your eating, exercising and social behaviour plus by whether you pay attention to the daylight and night rhythm.
Thirdly, caffeine might highly affect your sleep. That might sound too obvious or even ridiculous but once consumed, caffeine is fighting a chemical inside your body that is called adenosine. Adenosine is building up in your brain and increasing throughout the day basically telling you that you are getting a little more tired every minute of the day until you finally go back to sleep. Caffeine stays in your system for way longer than you might think, thus, according to Walker, „sleep will not come easily or be smooth throughout the night as your brain continues its battle against the opposing force of caffeine.“
Last but not least, there are two completely different sleep phases that we sleep through repeatedly each night: The first one is the non-rapid eye movement sleep (or NREM sleep), the second one is the rapid eye movement sleep (REM sleep). The later is the stage of sleep in which we dream. NREM sleep contains four stages of sleep. „Stages 3 and 4 are therefore the deepest stages of NREM sleep you experience.“ One ’sleeping-phase‘ is about ninety minutes long. There is a very nice and explaining illustration here. I personally recommend to either sleep 6, 7.5 or 9 hours and thus sort of count in ninety minute portions so that you do not have to wake up right in the middle of deep NREM sleep.
I hope this was helpful and a quick but informative overview. I certainly hope you did not fall asleep reading it, haha. Let me finish as I started by another (short) quote and with that send you off to restful, sound sleep.
„Sleep is the single most effective thing we can do to reset our brain and body health each day.“Matthew Walker