2010-05-05 09:41:24
Getting less than six hours sleep a night can lead to an early grave, UK and
Italian researchers have warned.
They said people regularly having such little sleep were 12% more likely to die
over a 25-year period than those who got an "ideal" six to eight hours.
They also found an association between sleeping for more than nine hours and
early death, although that much sleep may merely be a marker of ill health.
Sleep journal reports the findings, based on 1.5m people in 16 studies.
The study looked at the relationship between sleep and mortality by reviewing
earlier studies from the UK, US and European and East Asian countries.
Premature death from all causes was linked to getting either too little or too
much sleep outside of the "ideal" six to eight hours per night.
But while a lack of sleep may be a direct cause of ill health, ultimately
leading to an earlier death, too much sleep may merely be a marker of ill
health already, the UK and Italian researchers believe.
Time pressures
Professor Francesco Cappuccio, leader of the Sleep, Health and Society
Programme at the UK's University of Warwick, said: "Modern society has seen a
gradual reduction in the average amount of sleep people take and this pattern
is more common amongst full-time workers, suggesting that it may be due to
societal pressures for longer working hours and more shift-work.
"On the other hand, the deterioration of our health status is often accompanied
by an extension of our sleeping time."
Five hours is insufficient for most people
Sleep expert Professor Jim Horne
If the link between a lack of sleep and death is truly causal, it would equate
to over 6.3 million attributable deaths in the UK in people over 16 years of
age.
Prof Cappuccio said more work was needed to understand exactly why sleep seemed
to be so important for good health.
Professor Jim Horne, of the Loughborough Sleep Research Centre, said other
factors may be involved rather than sleep per se.
"Sleep is just a litmus paper to physical and mental health. Sleep is affected
by many diseases and conditions, including depression," he said.
And getting improved sleep may not make someone better or live longer, he said.
"But having less than five hours a night suggests something is probably not
right.
"Five hours is insufficient for most people and being drowsy in the day
increases your risk of having an accident if driving or operating dangerous
machinery."
Story from BBC NEWS:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/health/8660373.stm
Published: 2010/05/04 23:11:45 GMT