The top five sleep myths

1. I can catch up on lost sleep during the week by sleeping in on the weekends.

False. Sleeping in on the weekends may help you feel more energised, but it won’t fully restore your mental performance. A study presented at the 2011 Meeting of Associated Professional Sleep Societies in the USA examined the brain function of subjects who netted six hours of sleep during the week and then had two nights of ‘recovery sleep’.

“After one work week of mild sleep deprivation, two recovery nights were adequate in improving sleepiness but not performance,” said lead investigator, psychiatry professor from Penn State College of Medicine, Dr Alexandros Vgontzas. The bonus kip-time was not enough to reverse the cumulative effects that sleep loss inflicts on the brain’s ability to function, he says.

2. Power naps can revive me after a period of sleep deprivation

Only kind of. According to the National Heart Lung and Blood Institute in the USA, there’s evidence that naps (up to an hour long) won’t completely make up for a night of poor sleep, but they can improve your mood, alertness and work performance.

“One study found that a daytime nap after lack of sleep at night did not fully restore levels of the blood sugar to the pattern seen with adequate night-time sleep,” it writes.

The Institute’s advice on napping: keep yours to 20 minutes. Any longer and you may have trouble waking up. And also, avoid late arvo naps – these can disturb the main performance, namely your night-time sleep.

3. The older I get, the less sleep I need

False. This myth has had some serious airtime, but it holds no weight. As adults – even elderly adults – we still need between seven and nine hours of sleep, but the quality of sleep changes. Essentially, we spend less time in ‘deep sleep’. Our sleep is lighter and we wake more frequently during the night.

“Older people don’t need less sleep, but they get less sleep or find their sleep less refreshing,” advises the Institute.

4. Teenagers need the same amount of sleep as adults

False. They need more; 9-10 hours’ sleep each night. According to the Institute, the hormonal shifts that beset teens throw their body clocks out of whack – so they feel the urge to go to bed later and wake up later, too.

As a result, because school kicks off early, often teens end up with just seven and a half hours’ kip.

Tip: if your teen is often sleepy during the week, encourage an earlier bedtime so he or she can catch more hours under the covers.

5. Men and women are created equal when it comes to sleep deprivation

False. Back to that study presented at the Associated Professional Sleep Societies meeting last year. This found that when women are sleep deprived, they cope better. Compared with sleep-deprived men, women short on sleep reported less sleepiness and less mental performance deterioration.

As Dr Vgontzas explains, in women, but not in men, any deep sleep experienced appears to have a protective effect on the brain. “Women with a higher amount of deep sleep can handle better the effects of one work week of mild sleep deprivation, and their recovery is more complete after two nights of extended sleep.”

References available on request