Getting ready for bed
What's happening in your body when you're winding down for the evening? Phil Sansom has been finding out...
Phil - You’ve had your dinner, and it’s getting late. And while you may not want to turn off the TV, your body is busy getting on with the business of sending you to sleep. In the absence of sunlight, your brain starts releasing a hormone called melatonin that makes you sleepy.
And is it getting a little chilly in here? As you get sleepy, and while you sleep, your core body temperature can drop by as much as 1 degree C. As for why this happens, it still remains a mystery. There is some evidence to suggest that this cycling of the body temperature helps to set the clocks of other systems in the body. Or it could be that it’s just more efficient from a metabolic perspective to be asleep and using the least energy when it’s cold outside.