Struggling to sleep? Why circadian health optimisation is crucial

Updated: Aug 27, 2020

Struggling to get to sleep? Most of us aren’t getting enough sleep, and that’s largely thanks to our ‘always-on’ lifestyles and culture. So, it’s time to ditch the distractions and regulate your internal body clock.

How sleep affects wellness

Want to ensure you’re firing on all cylinders? Sleep is vital for optimal brain functioning and for minimising general health risks. Skimping on sleep affects your brain’s frontal lobe (responsible for cognitive processes and decision making) and the thalamus (responsible for alertness and attention), so a poor night’s sleep can lead to a lack of mental clarity and poor decision making. Too little sleep can also result in your body releasing higher levels of cortisol, the stress hormone that stimulates alertness as part of a fight or flight response. Elevated cortisol levels can impact your metabolism, as it’s a signal to your body to conserve energy, hence why studies have shown that a good night’s sleep can be beneficial in maintaining a healthy weight. A lack of sleep also compromises your immune system; when you’re sleep deprived your body produces fewer cytokines, a small protein that controls and targets both infection and inflammation, so you’re more susceptible to illness and infection. In short, sleep is vital for good health!

Why circadian rhythms (internal clock) are important

Circadian rhythms are daily 24-hour cycles that control our body’s internal clock. The sleep-wake cycle is a circadian rhythm that’s predominantly regulated through our exposure to daily light-dark cycles. The sun’s rays stimulate us each morning, whilst energising us and keeping us alert during the daytime; conversely, darkness during each evening activates our feelings of drowsiness so that we enter rest, recovery and sleep mode. Technological advances, including artificial light and digital devices, have substantially changed our environment and disrupted our sleeping patterns, so the need to be consciously aware of our environmental disruptions and distractions has never been more important.


A good night's sleep
A good night's sleep

The different stages of sleep

Each evening your brain will move through sleep cycles, namely REM (rapid-eye movement) sleep and NREM (non-REM) sleep. On an average night, you’ll cycle through these stages four or five times.

  • Quiet sleep (NREM): The first part of the sleep cycle is non-REM sleep, which is composed of four stages.

  • Stage 1 (drifting off) - this stage occurs whilst you drift off to sleep and lasts for a few minutes; it’s easy for you to be woken up during this stage.

  • Stage 2 (light sleep) - during the second stage your heart rate will decrease, your core body temperature will drop, your body will start to relax, and you’ll enter a light stage of sleep.

  • Stages 3 and 4 (deep sleep) - this is the deeper stage of sleep when the body starts to repair itself and the immune system is strengthened.

  • Dreaming sleep (REM) - the first period of REM sleep usually occurs approximately 90 minutes after you initially fall asleep. During the REM stage your eyes will move rapidly behind your closed eyelids, your breathing will quicken, and your heart rate will increase too. Your brain is much more active during this time, hence why you can have some vivid or intense dreams at this stage of the sleep cycle. Throughout the night each REM stage will get longer.

“Artificial light exposure between dusk and the time we go to bed at night suppresses release of the sleep-promoting hormone melatonin, enhances alertness, and shifts circadian rhythms to a later hour—making it more difficult to fall asleep.” Charles Czeisler, PhD, MD, Harvard Medical School and Brigham and Women's Hospital.


Establishing a sleep ritual
Establishing a sleep ritual

Supporting your circadian rhythms

Many factors can throw your circadian rhythms out of whack; the good news is that you’re in control of them. Being mindful of these factors and making a conscious effort to eliminate any disruptions or distractions, will help to regulate your daily sleep-wake cycle:

  • Managing your exposure to light – the production of melatonin, the sleep hormone, increases with the onset of darkness each evening in order to induce sleep. As melatonin is controlled by exposure to light, disconnecting from electronic devices an hour or two before going to sleep will help you to switch off. Using a sleep mask can also help you to block out the light and get into sleep-mode. Exposure to light in the morning is also crucial; try getting outside for a run or walk as the exposure to daylight will help you to fully wake up in the morning. During the winter months it can be very dark on a morning, so using a sunrise alarm clock will also help you to wake up at a consistent time each day.

  • Check the temperature of your bedroom – your room temperature should ideally be around 15°c-22°c to aid a good night’s sleep.

  • Minimise any noisy distractions – try to sleep in a quiet space; if you happen to have noisy neighbours or live close to a busy and noisy road then using earplugs can help you to switch off.

  • Having a regular bedtime – head to bed at the same time each evening, as having a regular routine will help you to wind-down and switch off.

  • Get up at the same time each day - avoid the urge to hit the snooze button and aim to get up at the same time each day, even on weekends. Having a consistent wake time helps to reinforce our circadian rhythms and will help you to get to sleep at a consistent time on an evening too.

  • Get regular exercise – ideally aim to get some exercise first thing on a morning so that you’re exposed to bright daylight, or a few hours before bedtime so that you burn off the stresses and strains from the day and start to wind-down.

  • Avoid drinking alcohol – whilst alcohol may seem to help you drift off to sleep more quickly, it blocks REM (restorative) sleep, so you’ll experience poor quality sleep and as a result you’re likely to wake up feeling tired and fuzzy.

  • Avoid caffeine and other stimulants before bedtime - caffeine (found in the likes of coffee, tea, chocolate, energy drinks, sodas or some painkillers) and nicotine (found in cigarettes or vape devices) are both stimulants and will make it much harder for you to drift off to sleep.

  • Ditch the late-night digital disruptions – learn to break any bad habits that may hinder your sleep, such as a late night Netflix binge, using your mobile to scroll through social media channels late in the evening, switch off your work emails and laptop so that you’re not working late.

  • Prevent any distractions, where possible - mute your phone notifications so they can’t disrupt your sleep during the night and if you have a pet that sleeps in your room and disturbs you during the night, consider moving your pet’s sleeping space to another room.

  • Make sure you’re comfortable – invest in a comfortable and supportive mattress, so you can rest easy.

  • Empty your mind – lots going on? Rather than going to bed with a mind full of information that could keep you awake, keep a notepad by your bedside and jot down all the things that may disrupt your sleep so that you clear your mind. This will also double up as a handy to-do list for the following day, so you can be productive and tick off the tasks that may be triggering stress or anxiety.

  • Maintain a regular sleep ritual – quiet and soothing activities such as taking a warm bath, setting the lighting in your home to a low level, reading a book, or practising mindfulness are all great ways to unwind. Choose the elements that work best for you and then aim to repeat this ritual each night as part of your regular wind-down routine.

Circadian health optimisation is crucial for your mind and body; consciously maintain a regular wind-down routine, sleep well and wish for sweet dreams!