Thursday, 1 November 2018

Understand blue light, our sleep cycles and how we sleep better

Understanding sleep - glasses and laptop on bed

I've just got a new pair of glasses. They are a bit special. Apart from being my first pair of transitions lenses, my new glasses have an extra added bonus that they help me fall a sleep better.  Confused? Well if I said they had blue light filters in them, some people might get a clue as to why. Understanding how we fall asleep and about our sleep cycles has helped our whole house sleep a bit better.

Sleep is extremely precious in our household.  One of our kids has even been to the sleep neurology team at Evelina's Children's hospital to help with his sleeping difficulties.   I'd heard of things like light and deep sleep and had an idea that we dream during something called REM and thought that was about it.

But David going to the sleep clinic taught me about how we sleep, the cycles and what could help our son and why as his parents, we were waking tired in the morning.  I've broken it down into falling asleep, stages 1-3 and REM.

Falling asleep

How does your body know it's time to fall asleep?  Well, there, a special center in the brain called the suprachiasmatic nucleus (SCN) which links to other parts of the brain that control hormones, body temperature etc that help us feel sleepy or wide awake. The SCN gets lots of external signals to help it turn on 'sleepy' feelings such as light, food, noise, and temperature.

For example, when there is less light going to the optic nerve to the SCN, this indicates it's getting dark and time for sleep.  So the SCN sends signals to the hypothalamus to make melatonin, the hormone that triggers sleep, which is usually released for around 12 hours.

Bright screens and particularly blue light at night can confuse these signals. Binging on TV after it gets dark can mean less melatonin and therefore more difficulty in falling and staying asleep. This is where having glasses with blue light filters has come in very handy. I'm surrounded by blue light screens throughout my day.  I'm busy on a laptop, I watch TV and even if I'm not directly involved my kids have blue light devices on all over the house.

The blue light filters on my glasses, cut out the blue light from the TV and devices to allow my body to naturally produce the melatonin it needs to fall and stay asleep.  Some people who have difficulty with falling asleep, like my autistic kids, can benefit from taking additional melatonin and slow-release medication in particular to replicate our own natural sleep aid.

In the end melatonin didn't work to help our kids sleep, but we looked very carefully at their bedtime routine, how we could reduce their blue light and how to make sure we were doing everything we could to help them get the sleep they (and we) needed.

Sleep cycles on fitbit versa

Stages 1-3

Stage 1 - This is your first initial falling asleep stage where you are still aware of your surroundings but your body is preparing for more sleep.  It's very easy to be woken from and doesn't usually last longer than a few minutes. If you've ever been one of those people who 'remembers falling asleep' it was probably remembering this.

Stage 2 - What most people think of as being 'light' sleep.  Again you are easily woken during this but it's doing more than the first stage.  Your body is processing information and may be running routine maintenance.  You come in and out of this type of sleep during the night and spent most of each night in this sleep stage.

Stage 3 - Deep Sleep. This is where you are really asleep - your brain and muscles relax and you don't really respond to external stimuli. I think of it as the 'physical rest and recuperation' part of sleep. You don't dream and your body does all it's deep repair work.  If you are woken from this, it's feel really rough.

Often known as a period of 'rapid eye movements' hence the acronym, this is the stage of sleep in which most dreaming occurs. Our eyes are not constantly moving, but may be related to what we see in our dreams.  It's part of the night where you consolidate your thoughts.  The rest of our body is quite still as we dream.

So what happens through the night?

Well we go through several sleep cycles usually lasting around 90 minutes or so in adults and about half that time in children. Over the course of the night, the amount of time we spend in a particular stage of sleep begins to shift.  Early in the night we should spend more time in each deep sleep stage and then later on in the night and into the morning we should spend more time in REM. We also wake each night but don't realise it. With my blue light filters, I've been able to produce that melatonin that I need to help me drift back to sleep without noticing.

With this information we were able to figure some things to help us understand what was happening with our family at night. We understood that David, our autistic son who went to the sleep clinic, wasn't usually waking before 1-2 am and so was probably getting his 'deep sleep' requirements.  This explained why he wasn't tired much during the day and why when waking at night he felt refreshed. He has lots of blue light throughout his day and this was part of the reason for trying him on melatonin.

When David was waking, my hubby and I had often only recently gone to bed.  As a result we were having our deep sleep interrupted (as you can see in the Fitbit sleep cycles above). A couple of things have helped us.  We've got routines to help us fall asleep and therefore get into deep sleep quicker. I've cut down my blue light with my glasses which is boosting my natural melatonin so I'm falling asleep and staying asleep better too.

We also helped David fall back asleep when he was waking by taking away his soothers (or dummies).  We discovered that when David would wake in the night he'd search for his soother and this would wake him up properly.  By withdrawing it, he didn't think it was missing, didn't search for it and went back to sleep.

We still have challenges (not least David's younger sister waking up now) but sleep in our home is certainly better than it was a few years ago.  Understanding a bit more about how we fall and stay asleep was fairly key in that.

This post included a giveaway which has now closed. 

Conditions: UK Residents only. Entrants must be aged over 18. Entry is via Rafflecopter. Entries can be made up until midnight on Friday 30th November 2018. One winner will be chosen from all valid entries at random the day after closing. The winner will be contacted within a week of the closing date and have one week to respond. The Prize is one Fitbit Versa. If unavailable an alternative product of similar or higher value sent included. No cash alternative. Any data collected will only be used solely for the purpose of contacting you should you win the competition and will not be used or stored by me for any other reason.  Check further details about Rafflecopter's privacy here or see my policy below. 

I was sent a pair of blue light filter glasses by to try for purpose of review.  I love them and am happy to include them and information about them in our post.


  1. I love my fitbit! I would love an upgrade. #triumphtanttales

  2. Sleep is so important for wellbeing and I am so pleased we know this now and can tap into its benefits. Never remember anyone telling me how important it was until in last year or so. I have always loved it though! Great giveaway too #TriumphantTales

  3. It is great that yu have been able to use these sleep patterns to help your family sleep a little better. I hope it improves some more for you.

  4. Good to know. Weird how easy it is to thorw out of whack! #KCACOLS

  5. This was full of helpful information. I have been debating on whether or not I want to ask for a Fitbit for Christmas. Thanks for sharing. #KCACOLS

  6. Very informative! I had no idea about the sleep links to autism.

  7. Shared. Interesting read about sleep. Fingers crossed for a win 🤩😂

  8. I'm not sure I'd want my sleep analysed because I'm certain I need more quality sleep! I do avoid blue light by reading my book before bed. Really interesting to read more about the sleep cycles. Thanks so much for linking up at #KCACOLS. Hope you come back again next time!

  9. This was such an interesting read. I find sleep and dreams such an interesting area of study, and was really interested in your experience of visiting a sleep clinic. And the glasses you have with the blue light filter sound brilliant, such a simple solution to the problem of blue light affecting our sleep! x #KCACOLS

  10. What a great idea. Sleep can be such a difficult one. I used to be an insomniac, and still occasionally have a broken night, but actually since having my little one my sleep patterns have totally changed. Getting the chance to study our family would be a great idea, so thank you for sharing this! #KCACOLS

  11. This is a great idea. I used to track my sleep and I also have blue filters on my glasses too. My issue these days is being woken up by random noises from neighbouring houses and not being able to get back to sleep #kcacols

  12. This is a really good article my mum struggles to sleep she goes on her phone and she has macular degeneration which needs to be operated on..very useful read thank you

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  14. Love the information in the post. Thank you. Me and my husband too have sleep disorders and cannot achieve deep sleep. Appreciate the info tips.


  16. Thanks for suggesting good list. I appreciate your work this is really helpful for everyone. Get more information at how to sleep lighter. Keep posting such useful information.



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