Sleep. For me, I consider sleep one of the most important pillars of our health. In fact, it may be the most important one, next to nutrition, mental health, physical well-being, and hydration. There are so many reasons why sleep is important and I wanted to dedicate the next few weeks on a series towards this fundamental topic.
Why Sleep is Important
Sleep is such a powerful tool. Why? Because it is the single most powerful performance-enhancing and health-providing activity to humankind. Sleep affects everything in our bodies. Both our mental and physical well-being, as well as a range of biological processes.

Sleep and Physical Health
Sleep is super important for our physical health. It lowers our blood pressure whilst we sleep (I actually find that incredibly cool!) and is also crucial for our immune system. Whilst we are sleeping, we produce antibodies that protect us from invading pathogens and germs. In fact, if you sleep less than 6 hours a night, studies have found that your are more than 4.5 times more likely to catch a cold. So if you want to support your immunity sleep is a very important contributing factor. What researchers have also learned is that sleep can wash our brains of toxins. There is something called cerebrospinal fluid, which washes in and out of the brain in waves during deep sleep times. Basically, this fluid takes out the metabolic trash in the brain and may even play a role in reducing your chances of Alzheimer’s disease or dementia.

Sleep and Mental Health
As important as sleep is for our physical health, it is also crucial for our mental well-being. We all know how it feels when you wake up after a day of not sleeping well. You are grumpy, you are moody, you are likely more hungry. All of this is because your hormones are out of balance and not “functioning” properly. You are also less likely bring your best in terms of cognitive performance. Sleep and waking up rested are necessary in order for us to feel happy.
Long-term, sleep is able to diffuse stresses that we have experienced during the day and allows our emotions to stay balanced. Research indicates that people with insomnia are 10 times more likely to suffer from depression and 17 times more likely to suffer from anxiety. Or, to put it the other way around, any improvement to your sleep will also directly (positively) impact your mental health.

The Different Sleep Cycles
Ever heart of a sleep cycle? Basically, it is a four-stage process that you go through multiple times each night. The quality of your sleep depends on (1) how much sleep you get, as well as (2) how restorative that sleep is. Cycling through your sleep cycles multiple times per night (between 4 – 6) smoothly is therefore also important. Each sleep cycle lasts about 90 minutes. The ones earlier in the night tend to be a bit shorter, and the ones later into your sleep cycle tend to be a bit longer.
The four stages of the sleep cycle are:
- Stage 1/N1 – this stage lasts fairly shortly and is basically the dozing-off phase. Body and brain activities start to slow down. If you are not disturbed during this phase, you can easily move on to phase 2. As the night progresses and if you tend to not wake up during the night, you will cycle through this stage faster and faster.
- Stage 2/N2 – this stage allows your body temperature to drop, slows down your breathing and heart rate, and relaxes your muscles. Your brain activity slows down. During your first sleep cycle, you tend to only spend about 10 to 25 minutes in this phase. This stage gets longer with every cycle though. About half of your entire time is spent in this cycle throughout one night
- Stage 3/N3 – this phase is known as the deep sleep phase. The one where it is fairly difficult to wake someone up from and the body is fully relaxed. Experts assume that this is the phase where your bodily repair processes take place, as well as its contribution to the immune system discussed above. Deep sleep may also contribute to insightful thinking, creativity, and committing thoughts to memory. This phase is the longest during the early part of the night. The longer the night, the quicker we move to the next stage
- REM – the rapid eye movement stage is where the brain tends to pick up again with regards to brain activity and mimics almost levels as if you are awake. At the same time your muslces are paralysed with the exception of the ones controlling your breathing, as well as your eyes, which can rapidly move (and hence the name for this stage). This stage is essential for cognitive function, memory, learning, and creativity. It becomes longer as the sleep cycles go on and adults spend about 25% of their entire sleeping time in this stage

How Much Sleep Do We Need?
There is no one answer to this question. On average we need between 7 to 8 hours a night. However, some adults may need slightly less sleep and some slightly more. A really good indicator is whether you feel refreshed when you wake up. Can you spring out of bed and feel good and can you maintain that feeling without slumps throughout the day? And are your emotions relatively stable on top of things? If the answer is “yes” you have likely found the right amount of sleep for yourself.

Should I keep Regular Sleeping Hours?
The answer to this one is a definitive yes. We have an internal body clock located in our brain which regulates all sorts of biological processes on time. This includes your appetite hormones, blood pressure, heart rate, as well as sleeping and waking. This internal body clock is kept “in check”(so to speak) by external factors that we establish (like going to bed and waking at similar times). It is also dictated with the rise and setting of the sun. The more regular this internal clock is kept, the more your body will be able to anchor you and produce the necessary hormones at each stage that put you both to rest and keep you wakeful and alert when the next day comes.
By the way, our brains are also hugely responsive to repetition. Your brain will recognize steps taken after a while and respond to this wind-down process. I have written an entire post about how to establish a good sleeping routine if you want to check it out.
I hope the above has given you some insight as to why sleep is important and necessary for us human beings. Next week we will continue and link sleep to nutrition 💕. Beautiful photo by Liz Vo on Unsplash.