Sleep – The three key regulators

sleep asleep Dr. Matt Barber

Sleep – the three key regulators

The health topic that got the most engagement with on Instagram is sleep!  It’s not surprising because sleep is so important and inadequate sleep is really common.

A report by the Sleep Health Foundation in 2017 showed that four out of every ten Australians aren’t getting enough sleep. It showed about half of those four are getting dangerously low levels of sleep. As in levels that contribute to heart disease, depression and other medical conditions. The other half are missing out of better levels of alertness, concentration and emotional regulation. Every day more than one Australian is expected to die from a motor vehicle or industrial accident caused from inadequate sleep.

You’re probably reading this thinking I’m going to talk about not having caffeine close to bed time or avoiding screens an hour before you go to sleep. I’m not. You guys already know all of that. I want to tell you about the three key regulators of sleep. (1) Sleep appetite, (2) Circadian Rhythm and (3) Arousal. These are three key things that determine how you sleep.

Sleep appetite

Sleep appetite is your body’s readiness to fall asleep. When you wake up feeling really refreshed that is the time your sleep appetite is at the lowest and as the day goes on it gradually increases. The biggest risk to sleep appetite is napping so be careful about spoiling your sleep appetite by napping. If you really need to nap set a timer for 20-30 minutes and don’t nap any longer than this.

Circadian rhythm

Circadian rhythm is your internal body clock which just so happens to be vulnerable to a lot external influences. It affects more than just sleep, things like blood pressure, body temperature and many hormones are subject to your circadian rhythm. Circadian rhythm is the reason why we have jetlag. The single most important thing you can do to keep your circadian rhythm in check is wake up at the same time every day. It’s actually way more important than going to bed at the same time every day. Sleeping in on weekends (even if you’re sleep deprived) will throw your rhythm out and waking up at around the same time every morning is the best way to recalibrate it.


The last driver of sleep is arousal, this is a really important one. We are all so busy during the day we rarely have time to process our day until our head hits the pillow and that’s when we start to think about today or tomorrow’s problems. So many of my patients have that ‘mind-racing’ phenomenon when they go to bed. There are two quick and easy fixes that might help this. First, don’t let this be your only time to think about today or tomorrow. Set a time before bed (and out of the bedroom) to think about the day – a journal is perfect for this. Secondly, don’t have an alarm clock in the bedroom. If you are lying awake at night noticing how late it is getting and worrying about being a wreck the next day it is guaranteed to worsen your sleep.


There is so much more to say about sleep, this is just the beginning. In other posts I’m gonna talk more about circadian rhythms, hormones and melatonin, useful sleep resources, sleeping pills, and different stages of sleep. Let me know if there is anything you in particular would like to know about sleep.



For more information on sleep there are some great resources at the  Sleep Health Foundation

You can access free cognitive based therapy treatment for insomnia at This Way Up