In the late 1800's the invention of the light bulb did an amazing thing for productivity allowing us to keep working after sunset. However with it came some unexpected health consequences that we may not have foreseen.
When we were cave dwellers the sun went down, we sat around the camp fire to stay warm and cook if needed and told each other stories from our days. The light from the fire gave off a healthy red glow which did not interfere with our circadian rhythm – which is sadly a different story to the light we now use to keep moving about at night time after the sun has gone down.
The newest form of residential and office light is an LED type of bulb which is highly efficient, lasts a lot longer than old fashioned bulbs but has one ‘dark side’ to it that similar to the invention of the light bulb isn’t just about the red light from our ancestors camp fire light and is in fact – BLUE LIGHT. Light is exists on a spectrum and purple/blue, which tells us it is day time and is at the opposite end of the spectrum to red.
Hence the idea of getting outside in the morning to signal the brain it is time to be alert and productive for the day.
Those LED lights we now have in our homes give off a large amount of blue light and this can be confusing for the human brain to the extent that it fools it into thinking it is still day time and so must remain alert. Roll on bed time and we may struggle to sleep fully and deeply as a result. That is because blue light inhibits a hormone called melatonin – which is our sleepy hormone which starts to kick in after sunset.
Here are my steps to locking in a solid circadian rhythm:
- Go to bed and get up at the same time 7 days a week (no weekend cheating or you may suffer social jet lag)
- Create an environment in the bedroom of absolute darkens – this helps to reinforce the message to the brain that it’s sleep time.
- Dim the lights at night time or even use blur light blocking glasses to filter out all the blur light from LED lights, mobile phone, TV’s and computers.
- Create a bedtime routine to help your brain and nervous system wind down. E.g. read a book, have a hot bath, listen to gentle music, do some meditation
- Enjoy your caffeine before 12 noon. As caffeine inhibits the sleepiness feeling. It also has a half-life of around 6 hours. So a full strength cup of coffee at 3pm is the same as having half a cup at 9pm and expecting to go to sleep soon after – some people can do it but no many!