Too hot or too cold to sleep?

A sudden dip in the temperatures across Europe and a snowfall last night and it seems like the right time to write this post.

I woke up in the middle of the night the other night and couldn't get back to sleep for a while. I then realised that I was slightly cold. I didn't feel cold in that I was shivering, or my hands and feet were like ice blocks, but just slightly cold. I pulled a blanket on top of my duvet and was asleep within 10 minutes, just that little bit of extra warmth making the difference.

There is a very narrow range for an optimum temperature in the sleep environment for humans, which is between 18 and 22°c (65 - 72°F). The body temperature dips at night to allow sleep and so being in a cooler environment helps the body achieve this. However if it is too cold, then your body is working to warm you up and therefore makes it difficult to sleep.
I was brought up in a home were central heating was sparsely used, so prefer a cooler sleep environment. I find it difficult sleeping in houses were there is 24 hour heating (which happens a lot in Europe with communal heating for a block of flats).
Of course if you were brought up or live in a warmer environment/climate you become used to higher temperatures, but when temperatures fluctuate over the year, you need to try and keep the bedroom temperature as steady as possible.

Here are some good sleep hygiene practices for the different seasons -

In Winter
- keep the thermostat cooler in the bedrooms (radiator thermostats help with this) or turn the temperature down half an hour before going to bed.
- try experimenting with layering - using different tog duvets and blankets as well as warmer bedclothes, pyjamas and bedsocks!
- when your partner has different needs, try using separate duvets or perhaps sharing a duvet and one partner having a light blanket over them as well.

In Summer
- keep the room as cool as possible during the day, closing the curtains to keep out the sun, blackout blinds etc.
- use a fan to keep the air circulating and put a container of frozen water in front of a fan
- avoid memory foam pillows as these can heat up the body.
- turn off or remove all unnecessary equipment, as these can heat up a room, even incandescent lightbulbs can heat up a room!
- if you use it, check the air-con is not too low, as too much of a drop can make it too cold to sleep.

Here in France the temperature can fluctuate between overnight lows of -12°C to overnight highs of 35°C, so over the year I employ many different techniques to try and maintain the best sleeping environment, in winter I have a fleecy undersheet, high tog duvet, blanket and sometimes a hot water bottle. This all gradually reduces to a sheet and fan in the high Summer.

If you're not sleeping too well then take a look at the temperature in your sleep environment and see if there anything you can change to get a better night's sleep.

Sweet dreams!