It’s full of fascinating facts and uses the phrase “to eke out the very last quantum of sleepiness” which is just lovely.
Until recently, people living above the Arctic circle slept much longer in winter than in summer. There are reports from the 1950s of Inuit sleeping up to 14 hours a day during the darkest months compared with only 6 in the summertime. Given the opportunity, we can all learn to significantly increase daily sleep on a more or less permanent basis. When it is cut back to normal we are sleepy for a few days, and then the sleepiness disappears.
Far from our being chronically sleep-deprived, things have never been better. Compare today’s sleeping conditions with those of a typical worker of 150 years ago, who toiled for 14 hours a day, six days a week, then went home to an impoverished, cold, damp, noisy house and shared a bed not only with the rest of the family but with bedbugs and fleas.
What of the risk of a sleep shortage causing obesity? Several studies have found a link, including the Nurses’ Health Study, which tracked 68,000 women for 16 years (American Journal of Epidemiology, vol 164, p 947).
The hazard, though real, is hardly anything to worry about. It only becomes apparent when habitual sleep is below 5 hours a day, which applies to only 5 per cent of the population, and even then the problem is minimal. Somebody sleeping 5 hours every night would only gain a kilogram or so of fat per year. To put it in perspective, you could lose weight at the same rate by reducing your food intake by about 30 calories per day, equivalent to about one bite of a muffin, or by exercising gently for 30 minutes a week.
One of the lessons from sleep research is that we’re actually pretty bad at judging how much sleep we need and even how much we actually get.
This seems to be particularly the case for people with insomnia who tend to underestimate the amount they sleep and overestimate the time it takes them to drop off.
The article is great guide to sleep myths and how they’re addressed by the scientific research and surprisingly for New Scientist, the article is open-access.
NewSci staffer having sleepless nights over their closed-access policy or just someone asleep at the wheel? Answers on a night cap please…
Link to NewSci piece ‘Time to wake up to the facts about sleep’.