Is Seven The Magic Number?

It is possible that too much sleep is worse for your health than too little.

12:13 25 March 2015

Is it possible that the 8 hour sleep for which many people strive each night, could actually do us more harm than good?

We have assumed for a long time that we should all try to get 8 hours sleep a night but research now suggests that this is not the case.

It is quite commonly heard that too little sleep is connected with obesity, diabetes, high blood pressure and heart disease.  So surely more sleep is the answer? Not necessarily.

Research findings over the last decade, has found that there is an optimum sleep time of 6-8 hours and people who fall outside this parameter are at increased mortality risk than those who have sleep patterns that fall within this boundary.

Over a million candidates took part in a study by Prof. Franco Cappuccio, who is a professor of cardiovascular medicine in Warwick University.  The participants were questioned as to their sleeping habits and then followed up over time.

He considered participants who sleep less than 6 hours, more than 8 hours and those who sleep 6-8 hours.

On following the participants up, he found that 12% more of the shorter sleepers and 30% more of the longer sleepers had died that those who slept 6-8 hours.  He argues that this suggests more sleep is worse for you than less.

Possibilities the professor considered for this were that the some of the longer sleepers may have been depressed or using medication.  He amended this and the connection remained.

Another suggestion for this was that the need of some people to sleep longer is the result of an underlying illness which as yet has not shown any other symptoms.  It was suggested that this was the reason for the mortality rate rather than the sleep itself.

Professor Youngstedt of Arizona State University, found that people who slept for longer had increased inflammation and more pain and aches possibly due to the lack of motion for so long.

However it is very difficult to accurately report how long you have slept for and people tend to overestimate this.

It seems that on average, over time, the median amount people tend to sleep for is 7 hours.  This suggests that this is a more natural requirement for the brain.

As of yet there is no hard evidence that sleeping too much makes you die sooner.