Luton you are quite openly expressing your personal opinion about my post which I don't believe should be one of moderator prerogatives. Still thank you for letting me democratically express my opinion even if I'm a fool.
Back to the topic it could be interesting to know about this:
Sleep Duration and Longevity
Don't Sleep Too Short or Too Long
By Mark Stibich, Ph.D., About.com Guide
Updated October 30, 2008
Can your sleep habits impact your longevity? Research has shown that if you sleep too much or not enough, your risk of death increases significantly. This could be a result of the impact of sleep itself on overall health or it could be because other diseases impact both longevity and sleep duration.
Sleep Duration and Mortality - The Study
In one study, researchers followed over 21,000 twins for more than 22 years. They asked questions about the twins' sleep habits and looked at their longevity. Twins make great research subjects because most of them grew up in the same environment and the have the same (or similar) genetic make-ups. This way researchers can isolate the impact of a behavior (say, sleep duration) to an outcome (like longevity). However, in this study, researchers decided to pool the twin data together - this lost some of the benefit of using twins as a study group. It is not clear why they did this, probably something to do with the way the data was collected.
The participants were asked questions at the beginning of the study and 22 years later. The questions concerned sleep duration, use of sleep medications, and quality of sleep. Researchers were also able to collect data on each participant about their longevity.
The Results - Sleep Duration Linked to Longevity
What the researchers found was that if people slept less than 7 hours a night or more than 8 hours a night, they had an increased risk of death. For short sleep women, that increase was 21% (men: 26%) and for long sleeping women, the increase was 17% (men: 24%). If the participants reported using sleep medications, their risk for death also increased. Women using them had a 39% increase in risk while men had a 31% increase.
Over the course of the study, 30% of the participants changed their sleep habits. The most common change was to shift from stable sleep to short or long sleep. These shifts were also linked to increased risk of mortality.