Sleep
We all know sleep is good for us and many of us want more, better quality sleep. Without sleep you can’t form or maintain the pathways in your brain that let you learn and create new memories, and it’s harder to concentrate and respond quickly.
Research shows that a chronic lack of sleep, or getting poor quality sleep, increases the risk of disorders including high blood pressure, cardiovascular disease, diabetes, depression, and obesity.
Here are some areas where research is giving us some helpful information on how we can improve things.
Light and sleep
Lots of research into sleep focuses on the importance of the sleep wake cycle, otherwise known as circadian rhythm. This is your body’s internal 24-hour clock and dictates your level of alertness, body temperature and levels of hunger at different times in the day. Light is one of the most important things that will help to regulate your sleep-wake cycle.
Lux is the measure most often used when talking about light. It is a measure of environmental light. The amount of light outside during the day will be between 50,000 and 60,000 Lux. Indoor light is much lower, typically 500-1000 Lux. Even with a light box which is specially designed to provide light at higher levels you are only getting between 2000 and 10,000 Lux.
We should all be ideally getting 2000+ Lux for approximately 30 mins as close to the start of our day as possible in order to get our body awake.
The more daylight exposure you can get, the better it is for your sleep-wake cycle.
Some more recent research has shown that concern over night-time exposure to light may be mitigated by better exposure to light (ideally natural) during the day.
Many large research studies show us that night-time light exposure is associated with poorer sleep and increased levels of some mental health conditions such as depression and thoughts of self-harm and that increased levels of daylight are protective against these. So, if you want/need to have some light exposure in the evening make sure you get lots of time outside during the day to help mitigate the harmful effects of the evening light.
Historically before artificial light (and in cultures today who have no artificial light) humans had a biphasic (or polyphasic) pattern of sleep - they would sleep in 2 or more distinct blocks rather than 1 longer block like we tend to now. This is good to know as it helps not to get too worked up when you wake in the middle of the night - just try to remember that it is part of your programming and you will be able to get back to sleep. Reverting back to biphasic sleep is more common in the winter months due to the reduced hours of daylight. Generally getting up and doing something relaxing and in low light will help rather than lying in bed and worrying about not sleeping!
Temperature and sleep
Your core body temperature goes down as much as 1 degree by about 4am. The evening drop in your core body temp is a signal to the body that it is time for sleep. So promotion of that drop in temperature can help us get to sleep. Many sources advise a warm bath or shower before bed to help with sleep but thinking about the body temperature needing to be lower surely this feels counter intuitive? Actually, a warm bath will cause vasodilation (widening) of the more external blood vessels in order to cool the blood down so it does help reduce body temperature. A warm bath can also be relaxing which can help with winding down before bed.
Don’t make it too hot in your bedroom - consensus is about 18-20 degrees is a good temperature. (Data shows that this may be more like 20-22 degrees for older individuals). If you are struggling to sleep try a slightly cooler temperature in your bedroom - or a lighter duvet.
Males and females also tend to like slightly different temperatures - women on average like a slightly warmer temperature. This can be tricky when sharing a bed! Try a Scandinavian approach with 2 single duvets - of different thicknesses.
Chemical sleep aids
Prescribed sleep aids tend to work on the chemical neurotransmitter in the brain GABA. GABA is the main way that the body reduces its transmission between nerve cells. So most chemical sleep aids work by increasing levels of GABA or increasing sensitivity to GABA.
Examples of medications that can be prescribed by your doctor are temazepam or zopiclone. These medications will produce a sedative effect - but sedation is not the same as sleep. They will not provide a complete biological mimic for sleep. Some will actually reduce memory consolidation and formation of new neural pathways that are some of the main functions of our brain when we sleep.
So, short-term use of these medications can be really helpful to correct your sleep in an emergency situation - for example the death of a loved one or a traumatic event, but their longer-term use can actually be harmful. Some studies actually show a link with long term use of sleeping tablets and dementia. The best way to improve sleeping long term is to improve sleep behaviours and routines.
There is some emerging evidence that magnesium can be useful as a more natural sleep aid. It has been shown to increase the body's responsiveness to GABA and additional magnesium in the diet or supplements can improve sleep.
Melatonin is another medication that can be used to help with getting to sleep. Melatonin is a biological marker of dark and so helps the body realise that it is night time and therefore helps with initiation of sleep.
Sleep - conclusions:
Simple tips:
Routine - go to bed and get up at a similar time each day if you can
Make your room a restful place
Reduce light in room - black out curtains/blinds or eye mask
Limit noise if possible - or wear ear plugs
Relax before bed - limit screens - read a book, take a bath, listen to music
Breathing exercises - focusing on prolonging your exhale
Journal - some gratitude
Avoid caffeine and sugary drinks in the evening
If you are really struggling to get to sleep - get up and do something else for a little while then try again
Advanced:
Sleeping in separate bed from partner
Importance of daytime light - ideally getting some natural light as close to your wake up time as possible.
Reducing evening light - Ideally 30 mins-1 hour of no screens before bed (not only does this reduce evening light exposure but it will limit alertness - like that caused by looking at emails or watching something dramatic on TV.)
If you are struggling with sleep and need some support I can help. We can look at your sleep routines and ways you can make changes that best suit your individual needs.
This blog is to give you information and some ideas based on scientific evidence about how to make changes to improve your sleep, but not as specific medical advice. If you need specific medical advice it is best to speak to your own doctor/GP.
Links to further reading:
https://www.bbc.com/future/article/20220107-the-lost-medieval-habit-of-biphasic-sleep
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4763365/
https://www.nature.com/articles/s44220-023-00135-8
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3427038/
https://academic.oup.com/sleep/article/43/Supplement_1/A464/5847198
https://onlinelibrary.wiley.com/doi/10.1111/jsr.13621 - The circadian system, sleep, and the health/disease balance: a conceptual review
https://www.pnas.org/doi/full/10.1073/pnas.2101591118 - Dim light in the evening causes coordinated realignment of circadian rhythms, sleep, and short-term memory
https://content.iospress.com/articles/journal-of-alzheimers-disease/jad221006
https://www.sleepstation.org.uk/articles/sleep-aids/magnesium/
