loss of sleep One in four people in the UK are estimated to suffer with insomnia. And if you’ve ever had a sleepless night, but spent your time ‘resting’ by lying in bed you might feel cheated when you still feel downright exhausted the next day. Well, according to researchers from the University of Colorado, that’s because not being able to sleep uses up a surprising amount of energy even if you don’t do anything in those wakeful hours. Just one night of missed sleep is the equivalent, they say, of walking a little less than two miles.
You’d think that if you’re lying down in bed, not using your muscles to stand, walk or even sit, your energy expenditure would be similar to that of when you are asleep. But, say the researchers, their findings show that when people are awake in bed they expend 135 extra calories that they don’t if they actually manage to nod off, not to mention the other healing and restorative process that occur when you’re asleep.
That number of calories might not seem like an awful lot, but even the researchers were surprised to find that it was more than they had estimated. Furthermore, the study participants were only allowed to read, talk, or watch TV during their sleep deprivation periods – the researchers point out that if a person were to move around or get up, the energy expenditure would be even greater.
But don’t think that a night of no sleep is a free and easy way to burn some excess calories and lose weight, it’s not. Other studies have shown that sleep deprivation actually makes weight gain more likely as it affects the production of a hormone called leptin, which tells the brain when you’re full. When you haven’t had much sleep, it doesn’t function in the same way, leaving you feeling hungry when you’ve already eaten enough.
People aged over 70 tend to sleep more lightly than their younger counterparts, but they also need fewer hours per night.
First published January 6, 2011