Is Six Hours Sleep a Night Really Enough?
Yes, you have heard it all before. A lack of sleep is bad for your health, both mentally and physically. But the question is, just how much sleep is enough? Is six hours okay, or do you really need eight, as has long been suggested?
The fact is that there is no easy answer. Back in 2010, a small study conducted by a psychologist at the University of California San Diego caused a stir because it challenged the notion that the standard 'you need eight hours of sleep a night' was incorrect, suggesting that just 6.5 hours was enough for most adults instead. The study was widely embraced at a time when the 'work, work, work' mantra was especially popular.
The Six Hour Proclamation Is Challenged
So was that study right? According to another, larger, more recent study, not exactly. This study, conducted by three very respected sleep medicine experts, tested the theory by taking a group of 48 volunteers willing to spend two weeks in a sleep lab and dividing them into three groups.
The groups were allowed 4, 6 and 8 hours sleep respectively for two weeks, with one unlucky group - the four-hour folks, also being told not to sleep at all for a period of 36 hours (ouch)
Over the course of the two weeks, each test subject was interviewed every two hours (when not asleep) to determine how they were doing mentally via a series of cognitive tests. Subjects who got only four hours a night did worse on their cognitive tests each day. The group who got six hours of sleep seemed to be holding their own, until around day ten of the study. The eight-hour folks did just fine.
And then came the kicker. During the last few days of the study, the subjects who were restricted to a maximum of six hours of sleep per night showed cognitive performance that was as bad as the people who weren’t allowed to sleep at all. Getting only six hours of shut-eye was as bad as not sleeping for two days straight.
There was more. As the researchers spoke to the six-hour group they realized that most of them didn't even realize how badly their cognitive test performance was. They thought they were doing OK and were failing to recognize that they were in serious mental decline.
The conclusions drawn by the researchers were that this cumulative lack of sleep - the lost two hours over the course of two weeks - was a real problem. Not that the negative effects of cumulative sleep deprivation is a new concept by any means, but experts agreed it’s rare to find research results that are so clear about the effects.
Finding a Way to Get Those Eight Hours
Ask most people who don't get eight hours of sleep a night why they don't and they'll say they are too busy, they have too much to get done. However, as it seems that what they are doing won't be as efficient if they don't get enough sleep then it seems like making an effort to find the time would be best. But how?
The final report related to the study had a few suggestions, including having a consistent bedtime, not looking at electronic screens for at least 30 minutes before bed and avoiding caffeine and alcohol for at least three hours before bed, the standard stuff you've been hearing for years.
But there were a few new ideas, including making use of a sleep tracker (even just the one built into the iPhone) to determine how much you are really sleeping and being open to taking active steps to improve sleep quantity and quality, including treating any insomnia issues. And while this all sounds like hard work if you’re functioning as if you hadn’t slept for two days straight because you are missing those two crucial hours, isn’t it worthwhile?