The Science Behind a Good Nights Sleep

Sleep – something majority of us do at the same time every day yet, something that many of us get don’t get enough of.

Falling asleep, staying asleep and waking up is a well-rehearsed dance between our hormones, neurotransmitters and our external environment. Ideally, we have our environment with a setting sun and decreasing sun and artificial lights, telling our hormones it’s time to settle into slumber, telling our neurotransmitters and brain cells “this is sleep, let’s get ready for the next day.” But what happens when this dance isn’t choreographed and why doesn’t sleep happen so easily?


One of the hormones that play a big part is adenosine; think of this one as the flag-waver that says, ‘sleep is near!’ Adenosine promotes sleep and suppresses our arousal, it builds up in our brain and central nervous system as soon as we wake up and once it hits a certain point of build-up, we start to nod off. This build-up of adenosine generally occurs after twelve to sixteen hours of being awake; therefore, the longer that we are awake the more adenosine will accumulate with sleep being the only method of clearance.

There’s a myth that you can prevent this sleepiness with caffeine. However, once your liver dismantles that barricade of caffeine, which works by blocking adenosine activity, you are hit with the sleepiness you had experienced prior to caffeine consumption, as well as the built-up adenosine that has accumulated throughout those hours of caffeination. The bottom line of adenosine is that you can’t prevent its build-up and sleep is the only way to clear it.

Serotonin & Melatonin

Serotonin and melatonin are another two big players in determining your sleep cycle; however, whilst they play together their roles are entirely different.

Firstly, serotonin is known as our ‘happy hormone’. It is our feel-good hormone that increases our positivity and relaxation. It increases in production and secretion in the morning and gives (most of us) that ‘get-up-and-go’ feeling, washing away the fatigue that would otherwise keep us in bed.

Secondly, melatonin acts similar adenosine telling your body when it is time to go to sleep. However, its production is in sync with our external environment. Once our body senses the day is winding up and light is turning to dark, its production and secretion are increased. We can see a steady increase in melatonin concentration from 6pm with it peaking at midnight, then declining and steadying throughout the day – ready to increase and peak again the following night. Every night, night in night out, melatonin does this.

Adding to the complexity of sleep, serotonin is the precursor for melatonin; this means that we need to serotonin to get the melatonin and without proper levels of serotonin, we won’t feel the need to sleep and we probably won’t get to sleep.


Enter cortisol. A steroid hormone produced by our adrenal glands that tells our body we are stressed or about to experience a stressful situation. It works with different parts of our brain to control our mood, fear and motivation. Contrary to melatonin, cortisol starts secretion in the morning and tapers throughout the day, eventually being replaced with the beginning of the melatonin secretion. Cortisol is primarily associated with ‘fight or flight’ instincts and we often

see patients that experience anxiety and depression disorders have higher circulating levels. With higher levels, we can see issues with feeling sleepy, getting to sleep, and staying asleep.

Why? Because cortisol will prevent the conversion of serotonin to melatonin – meaning our

body won’t get the message from melatonin that we would be getting ready to sleep soon.


To add insult to injury, on top of cortisol preventing us from the sleep we need, other internal and external factors are further preventing us. We can see prescribed medications, certain foods, caffeine, nicotine, alcohol, changes in daily schedules, exercise habits among a myriad of factors getting in the way of our rest.

But why do we need sleep? Why should we lay down and rest our head for the recommended 8 hours every night? There are things to do, that should be done before tomorrow and 8 hours of sleep putting a stop to productivity.

We need SLEEP!

We need sleep, we truly do. When we sleep it is essentially restoring our body to ‘factory mode’. It is clearing toxins, regenerating organs, repairing cells, rebuilding muscle, and solidifying learned information from the previous day. Sleep studies have found that during certain phases of sleep, brain cell activity turns on and off, and the pattern of this activity is similar to that when we are subjected to learning new material during the day. It is theorised that our brain replays memories from the previous day, helping us to make connections, consolidate emotions and remember information. This activity may also explain our dreams and why we have dreamt of someone or something that we encountered recently.

A few nights every now and then of disrupted sleep is tolerable. However, long term disrupted sleep can be the catalyst for other health-related issues. There might be feelings of daytime tiredness or sleepiness, irritability, depression, anxiety, difficulty paying attention or focusing on tasks at hand, changes in memory and energy levels.

Whether it is feeling sleep, getting to sleep, or staying asleep, Naturopathy is the natural path to identifying why your sleep cycle is not as it should be and how to restore it. We want you to feel rested when you wake up, ready to take on the day, and ready to rest when the time comes.