In a natural world we would sleep from 8-12 hours per night.  However the world that many of live in is far from natural.  We stay indoors away from the sun during the day and are surrounded by artificial lights at night.  All this lighting is confusing our bodies, and our sleep is greatly effected.

We want our cortisol levels to be high during the day and low at night.  Cortisol increases blood glucose which is a good thing when we’re awake and moving around.  But if cortisol is elevated at night, insomnia and restless sleep is the result.

But cortisol’s effect on sleep doesn’t end there.

Melatonin and cortisol are antagonist hormones.  When one is high, the other is low.  Melatonin is the hormone responsible for getting us into deep sleep and it helps keep us asleep.  So getting cortisol low at night is key to a good night’s sleep.

There’s one other hormone that effects melatonin.

Serotonin is the precursor to melatonin.  Serotonin needs to be released during the day so some of it can be converted to melatonin by bedtime.  Serotonin plays a role in helping us fall asleep too.

So how do we get all these hormones balanced?

Getting sunlight exposure during the day will increase both cortisol and serotonin.  Sunlight is 10-100X brighter than indoor lighting even on a cloudy day.  So going for a walk outdoors during day is the best way to increase these hormones at the right time.

Wearing sunglasses may make you look cool, but it’s confusing your body when it comes to producing hormones.  Your body will produce less cortisol and serotonin during the day, and impair your sleep at night.

Limiting your light exposure before bed will let your body know it’s night time and to help your body prepare for sleep.  Lower the lighting in your house to just the essential lighting 2 hours prior to bed.

Blue light impairs our sleep the most.  Most smart phones and other devices have a “night time mode” or there are free apps to download that will block blue light.  There are also blue light blocking glasses that are relatively cheap and easy to find online.  It is best to avoid screens at night.  But if that’s not practical, then make sure you block all the blue light you can.