Sleep is a vulnerable state. It’s important that we don’t go to sleep if we’re not safe to do so.
It’s also important that we don’t waste time better spent elsewhere through sleeping when it’s not the right time to do so. In our evolutionary past, daylight was precious to enable necessary work. Therefore, evidence of daytime, or the need to act, can inhibit our nodding off.
You can tell your body it’s time to sleep by creating the environmental cues of sundown, and give it signals of safety, with an absence of calls to action.
It is also important to live your days in a way that promotes sleep at night, and support your circadian rhythm... more of that, later.
So, imagine you’re in your evolutionary past, living in nature with no artificial light or electricity. How do you know that it’s bedtime?
You might notice that, towards sunset, the light is dimmer, of warmer tones, and the sun is lower in the sky. The temperature has dropped and the birds have stop singing. You may have your community or family gathered around you, relaxing after having prepared and cooked some food during daylight hours. All being well, there is an absence of things to do.
Things you can do
Make your cave cool
Imagine you’re in your evolutionary past, living in nature, with no artificial light or electricity. How do you know that it’s bedtime?
One of the clues you might notice is that the temperature has dropped.
You can recreate cool conditions by dropping the temperature of your environment (the optimum for adults is meant to be 18.3°) by turning down your heating, or opening a window in the hour or so leading up to bed.
You can also recreate cool conditions by dropping your body temperature - our core body temperature drops by 1-2° at night, which helps support melatonin release.
Having a warm bath or shower in the lead up to bedtime can be a good way to do this, after which your core temperature will usually drop. Make sure your hands and feet and head remain warm to enable the peripheral vasodilatation which is the other necessary part of the equation.
You might notice that, towards sunset, the light is dimmer, of warmer tones, and the sun is lower in the sky.
Light both affects our alertness, and our melatonin levels, the hormone important in supporting our sleep.
When you consider light, you can consider both its brightness (measured in ‘lux’), and its spectrometry or colour composition. Morning and midday light has lots of blue in it and, towards sunset, is much more orange in composition.
Figure: Towards the end of the day, the light is dimmer, and more orange in composition.
Towards bedtime, therefore, you want to create dim conditions, containing less blue and more orange light, and avoid bright (or blue) light.
You can do this by:
Dimming your lighting (take care to have enough to walk around safely)
Choosing warm tone bulbs rather than cooler ones
Filtering out blue light using blue light blocking glasses
Using dimmers, filters, “night mode” and greyscale settings on your devices
A good option is to have a digital sunset 60 minutes or so before bed. This both helps you avoid digital sources of light, and associated calls to action.
You can do this by:
Setting an alarm 60 minutes before bedtime to....
Set your morning alarm (consider an old school alarm clock)
Send any last messages and turn off, or put on airplane mode, all electronics – computer, phone*, tablet and TV
Starting your bedtime routine (see later sections).
When you’re actually in bed, you can reduce light by:
Using black out blinds
Putting masking tape over charging lights (or charging your devices in another room) and
Wearing eye masks.
*Make sure anyone who needs to be able to get hold of you knows how to do so
You might notice that, towards sunset, the birds have stop singing +/- the gentle hubbub of your family or community gathered around you.
You can recreate quiet conditions by turning down your music, loud noises or silencing notifications (incidentally, this also helps reduce calls to action).
Gentle background noise can also be useful, because it reduces the activity of our sleep spindles, it can give you something to focus on that isn’t busy thoughts and because it can replicate the sound of someone keeping watch (back to the sentinel theory).
Some people like:
Playing relaxing music, e.g. on Spotify
or sleep-scapes, e.g. on Headspace or Insight Timer.
Others use white/pink/brown noise via apps, links or machines (find out the difference between them, here), or like
Background noise like The Shipping Forecast,
Or stories, such as through Audible or Calm.
Finally, when you’re nodding off, if noise keeps you awake, you can try ear plugs.
Reducing signs that we aren’t safe, or calls to action (and introducing a digital sunset)
In our evolutionary past, before artificial lighting, daylight supported action. After all, there were limited activities that could take place in the dark. The night, therefore, was a time for rest, characterised by an absence of calls to action.
Nowadays, our most common source of calls to action, or of threats, tend to be digital:
Stressful work emails or messages
Hectic TV shows or computer games
The news
Social media…
Introducing a digital sunset can be a powerful way to remove this from our nights, as well as reducing our exposure to bright (or blue) light. Many people set a wind down alarm an hour before bedtime, when they set their morning alarm, send any last messages and turn off all devices or put them on airplane mode.
Apps can help do this for you, like Freedom; greyscale settings can make your phone less appealing, or airplane mode (or the trusty old off button!) can be useful to deploy. It can be even more helpful to do this as a household.
Sometimes it's difficult to switch off from a busy mind despite these efforts, in which case CBT for insomnia (CBTi) can be really helpful, e.g. The Sleep Project's Retrain your sleep programme, link below.
Winding down and sending signals of safety to our brains
One of the prerequisites to entering deep, restorative sleep is feeling safe. Many people report first night syndrome, where they’re in a new hotel room or new place, or sleeping with a new person, where they struggle to sleep deeply. This is because we’re not 100% sure that we’re safe and secure.
To feel safe, we need both an absence of calls to action or alarms (outlined in the last section), and active connection with regulating signals. We can actively give our body and brain signals that it’s time to relax.
Vagal manoevres like slower, deeper breathwork practices can help to regulate our autonomic state.
Connection with others is also a powerful way to calm ourselves down.
So, too, is anything that you find relaxing.
The more regularly we repeat these signals, the more conditioned our responses become. It worked for Pavlov’s dogs, and it works for us too! We call them Positive Sleep Associations.
So, pick an activity that you find relaxing.
Examples may be:
Having a warm bath or shower
Reading a paper book
Doing a breathing exercise, meditation or yoga Nidra
Spending time talking with your partner or family or friends, in person or on the phone
Doing mild-moderate movement like yoga
Journalling or doing a gratitude practice
Cuddling a pet
Listening to something, like an audiobook or podcast (nothing too exciting!)
Doing something repetitive like ironing
Making something, doing a craft or creative hobby
Going for a gentle walk.
Set a wind down alarm an hour before bed (or whatever you can manage) and, once it goes off, disconnect from your devices, get into your comfy clothes, and engage in your wind down activity.
If you really struggle to wind down, CBT for insomnia (CBTi) can really help.
Our sleep-wake cycle is primarily governed by our circadian rhythm, but another important player is adenosine. This neurotransmitter builds up during our waking hours, creating ‘sleep pressure’, and is then depleted again during sleep.
Caffeine blocks adenosine receptors, reducing our awareness of how sleepy we are. Individual sensitivity to caffeine is highly variable, but if you are caffeine sensitive, avoid having caffeinated drinks or foods within eight hours of bedtime. You can find out more about what contains caffeine here.
Because adenosine is depleted (converted back into ATP) during sleep, naps reduce our adenosine. Some people are excellent nappers, while others they find they then can’t sleep at night if they’ve napped too long or too late.
If you are quite sensitive to naps, one idea is to keep them less than 30 minutes (the magic length is 26 minutes, according to NASA!), and another is to try not to nap within about eight hours of bedtime (e.g. after 2pm if you tuck up at 10pm).
Managing shifts
Shift workers are particularly prone to sleep issues. You can find a blog on managing shift work written by Dr Chasser, here. You can also hear more in our Conversation with Experts.
In general, her advice is:
With a one-off missed night, stick to your normal routine, with a 2–3-hour nap as early in the day as possible. Maximise daytime light exposure, exercise and eat as normal, and wind down for bed at the normal time. Having a consistent bedtime routine provides cues to switch off and fall asleep, even after a night shift.
To transition between blocks of nights and days:
Your circadian rhythm can only shift by 60–90 minutes per day. Support this by recruiting light and dark, the timings of your meals and exercise, and potentially adding exogenous melatonin, with professional advice.
As always, this is not designed to replace advice from a sleep or medical professional. Courses such as Retrain Your Sleep can be very helpful, link below, and there is a link to a more detailed three-part blog "The shift work survival guide", below.
This is intended to be a place where busy healthcare professionals can come to find resources to support their fulfilment, productivity, health and performance.
Is there anything missing that you’re looking for? Or anything that has been useful for you that you would like to share? Any niche requests for recommendations? I would love to hear from you.
