Let there be dark!

It’s April which means it’s a perfect opportunity to develop some really good habits just in time for summer! This month’s blog is about blue light. This isn’t 'new' news but sometimes it’s important to remind ourselves every now and then of what we may already know but either have forgotten, chosen to think about at a later date or just ignored.

Back in the day people went to bed when the sun set and got up when the sun rose.  It had been like that since the start of time.   If you think about it, it’s only relatively recently that we’ve had light at the flick of a switch.  And going to bed when it got dark was exactly what I did as an expedition medic.  It wasn’t on purpose, it was just that with no gadgets, TV or artificial lighting there just wasn’t much else to do.  Of course, I could have sat in the dark and listened to all the jungle noises around me but that wasn’t too appealing.  I would often go to bed without even knowing what the time was.  All I really needed to know was that it was dark so it was bed time.  After only a few days I found myself waking up shortly after sunrise.  I felt great, I really did.  On the odd occasion I did check the time, I seemed to be going to bed at 8pm and waking up around 5am. 

But in normal life we don’t live like that.  We’ve got iPhones, iPads and laptops usually all within an arms reach - all the time. Hands up if you check Facebook, Twitter or LinkedIn, reply to ‘really urgent’ emails or read the news all from the comfort of your own bed?  Or use the alarm function on your smart phone?  You may even be reading this from bed.

And just how much harm can this habit really do?  Surely clearing all our inboxes and checking nothing really awful has happened in the world before we fall asleep, should mean we have a better night’s sleep - right? Wrong.  Bed time and the hours leading up to it should be winding down time, rest and relaxation time.  We are not designed for stimulation, stress and anxiety before sleep.  We’re also much more likely to make mistakes at night and send emails we would never ever have worded that way if we’d only have put off writing them until the morning.

Light can disrupt our natural sleep-wake cycle, also known as our circadian rhythm.  Blue light is particularly good at this.  We need blue light during the day to keep up awake, alert and focused but at night it can be detrimental.  And electrical devices with screens as well as energy saving light bulbs are the biggest culprits.   Sleep and mood are very closely linked meaning that poor sleep patterns really can have a major effect on your general well being. 

We don’t know why light exposure at night is so bad for us but even dim light suppresses melatonin, a hormone which is essential for regulating our circadian rhythm.  And there have been some recent studies suggesting a link between low levels of melatonin and cancer, particularly in long term night shift workers. Studies have also demonstrated a possible link between night time light exposure and heart disease, diabetes and obesity.  There is plenty of ongoing research into these potentially preventable, global chronic illnesses, including their causes.

We have to remember that just because we can check our phones any time we want to, doesn’t mean we should. So, why not try turning off all your gadgets at least an hour or two before bed, buy an an old fashioned alarm clock (you know, the type you had at school) and leave your phone in the living room?  Self discipline and self control are difficult but with practice it all becomes second nature.  And although research is wonderful, we have to rely on our common sense too.  After all, it's bright during the day and dark at night for a reason.