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Sleep Less, Live Longer
Linuxathome writes: "The Washington Post carried an article describing the results of a study linking the average amount of sleep one gets per night with his/her life span. It appears that those who sleep less than 8 hours a night, live longer (optimum is 7 hours). The study (link to the abstract) was aimed at looking at the mortality rate of those suffering from insomnia. But rather than associating insomnia with increased risk of death, it appears that sleeping more than 8 hours carries a much higher risk."
it seems from the report that the data are based on actual sleeping habits. this is to say that the time spent sleeping is, if anything, a symptom, not a cause. lots of rich people fly to Paris every day. this does not mean that flying to Paris every day will make you any richer.
-- Rolf Lindgren, cand.psychol
I would guess that many healthy persons lead busy lives and therefore have less time for sleep. Whereas some people with poor health may need more sleep.
Correlation is not causation.
Mea navis aericumbens anguillis abundat
...correlation is not causation. Who sleeps more than average? Old people, sick people, and depressed people. I'm not surprised to find out they have a shorter life expectancy.
FreeBSD - the power to serve.
If I could tattoo one thing on everyone's head, it'd be: "Correlation does not equal causation!"
This study does not mean that if you sleep less, you will live longer. A correlation has been found, that's all. Maybe people who sleep less have better circulation, also linked with long life. Or maybe the space aliens who shorten life spend two hours a night doing it.
Point is, we don't know what's causing this effect, at least not from this article.
Something to really keep in mind when looking at psychological/physiological studies is that correlation and causation are two different things. In order to show causation, you need to do more than just show that two things are correlated. Just becuase those that happened to sleep less tend to live longer, doesn't mean that if you sleep less you'll live longer.
One of the best examples of the difference between correlation and causation is that when ice cream sales go up murder rates also tend to go up. So if you start eating more ice cream will you be more violence prone? Nope, it's just that in the summer both ice cream sales and murder rates happen to go up. Must be the heat or something.
The report seems to come to the conclusion that just because people sleep less and live longer, the former causes the latter. It seems much more likely to me that the amount of sleep you get is indicative of what type of lifestyle you lead. Active people are less likely to oversleep and active people usually live longer. Also, depressed people usually sleep more than happier people, and depression can be linked to whole range of health problems that can affect your lifespan.
;)
Another possibility is that people who sleep less get more done, and are therefore more likely to be successful in what they do. This means that they would have a higher standard of living, leading to a longer lifespan. These are just ones I've come up with off the top of my head, so I'd say that less sleep does not lead to a longer life, but just is indicative of a lifestyle that would.
Oh, and when you're awake you can watch for bears and enemies attacking your cave. Natural selection probably favors those who sleep less
---- El diablo esta en mis pantalones! Mire, mire!
Quoting the article:
"The amount of sleep you get impacts how alert you are, your risk for accidents, how you perform at work and school," said James Walsh, president of the National Sleep Foundation (...)"There's much more to life than how long you live."
Bullseye. Interestingly, the article does not specify exactly how more sleep would decrease your lifespan.
Hey, if I can sleep 9 hours a day, be rested the next day, and live to be 80 and die, I will do it! Is there really anyone who would want to sleep 6 hours a day, be constantly tired throughout their lifetime, and then die at an age of 100 where last 20 years where spent in a bed with bunch of tubes going from their body and the 'beep...beep' sound of the EKG machine at all machine?
Makes me wanna sleep in more. And take naps. Three times a day.
...Studies found that many people undergoing chemotherapy eventually die of cancer. The number was so high, in fact, that the only conclusion we can draw is that chemotheraphy causes cancer.
And tonight at 10: "Tylenol: headache in a bottle?"
"Your superior intellect is no match for our puny weapons!"
Is that "Causality is unproven." in the study. So while they may be able to say that there is a correlation between 7 hours of sleep and longer life spans, it is not deterimined whether the 7 hours of sleep is actually causing longer life.
It could instead be something completely unrelated to sleep, but rather related to some other behaviour that the 7 hour sleepers engage in.
I agree completely with roffe.
Think about it, who do you know that sleeps 8+ hours a day, other than the elderly and sick (both groups who at more likely to die than the average person)? And from my experience, the "average person" generally has more important things to do than spend 8+ hours a day sleeping. So as roffe said, sleeping 8+ hours a day is more likely a symptom of someone trying to maintain their health, because they are in danger of dying.
To put it another way, when I had mono I was sleeping 12 hours a day, and the hours I was awake, it felt like I was dying. And it wasn't like I had to force myself to sleep, my body was naturally making me sleep longer so I wouldn't end up dying. And gee, would you guess what? When I got better, I went back to my normal 6-7 hours of sleeping!
Does anyone want to fund my study? I'm going to see if age has anything to do with death.
Kurdt
I'm not anti-social. Just pro-technology.
This is another case of the wrong conclusion being drawn from statistics.
I'll give another example:
People living near HV power lines have a higher chance of getting cancer.
Incorrect conclusion:
HV power lines cause cancer.
The failure is not looking at the whole situation. Further investigation reveals that most people living near HV power lines also live alongside superhighways, and the cause of their higher risk of cancer is exhaust fumes.
In the case of sleep: most people who sleep more than 8 hours a day are unhealthy "slobs" who also eat badly and don't get any exercise.
People who sleep less than 8 hrs a day are usually succesful people who also happen to enjoy sport and a good diet.
Alot of the "layabout" types I have met seemed far more interested in spending 12+ hours in bed than actually doing anything with there life.
It isn't just a lack of joie de vivre; hypersomnia (sleeping a long time) can be a sign of serious chronic illness such as major depression.
The press is picking up on this as a "sleep is bad for you" story. In fact, another interpretation that fits the observation equally well is that health people require less sleep than people with chronic illness. In that case, it would be very unfortunate if people take this to mean they can improve their health by reducing the amount they sleep, because this would very likely injure it.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
If this correlation is true, what controllable factors cause a person to sleep longer each night?
Some of the answers are well known:
All interfere with your body's ability to reach the deepest levels of sleep, so it takes longer to have the same amount of rest. At least two of the three factors are also associated with shortened lifespan.
Is the study totally worthless? No. It proves that you don't need to subject yourself to a dozen separate tests to determine how well you are managing these long-term risks - keeping track of the number of hours you sleep is sufficient.
For every complex problem there is an answer that is clear, simple, and wrong. -- H L Mencken