55 replies to this topic

[Live Forever]

I know there have been discussions here before on sleep, but I just ran across this short article on the proper amount of sleep that is required for health and longevity:
http://www.time.com/...-full-healthsci
(there is a link to the audio interview from someone from California's Scripps Clinic Sleep Center on the left side in the middle)

Evidently, the optimal amount of sleep is between 6.5 hr. and 7.5 hr. a night. More or less than that is unhealthy, but it is not known if the amount of sleep leads to the health effects or other factors that lead to the health effects also cause the sleep time. (in other words, it isn't yet known if it is a cause or an effect)

Does anyone have any thoughts or a link to the study they discuss?

[Brafarality]

Studies come and go.
Support buttresses one day and falters the next.

But, for the moment, I am feeling immodest...
I got this one in 1998, so I'm hoping it stands the test of time!

Ode to Sleep

Cheers.

[edward]

The problem with studies like this that they show correlations not causations. To say that people (not in a lab under controlled conditions their whole life) who sleep 6.5-7.5 hours a night live longer than those that sleep less than 6.5 and more than 8 doesn't really mean anything. I am not going to write a lecture on statistics 101 in one post but this is a common mistake among people trying to interpret studies. Basically there may be other reasons why these people end up sleeping 6.5-7.5 hrs, maybe these are the productive healthy individuals who because of work and family obligation can only get this amount, thus they are preselected as high functioning possibly genetically above average people. Those who sleep more than 8 hours may be underemployed, have long standing illnesses, chronic fatigue, depression or other issues that make it necessary to sleep more and thus recover more, and they will live shorter lives because of these other problems.

What if we took the 6.5-7.5 hour preselected sleeping group and made them sleep 9 hours, would they live even longer, my thought is maybe so, would they live shorter lives, probably not. There is evidence to suggest that more sleep leads to better hormone profiles more repair of tissues etc. which is why people in distressed conditions naturally sleep more, there bodies are trying to get these benefits so that they can get out of the imbalanced state.

Then there is the whole bias in reporting, self reporting of sleep habits, eating habits etc. are notoriously inaccurate.

[brokenportal]

I would just have to second edwards entire post. I agree completely. Are we wrong?

[Matt]

Agree with Edward totally. I'm surprised the researchers have not mentioned this. In my opinion this is a very likely, and very plausible reason for the different requirements in sleep. You hear all the time how people go on CR need less sleep. Sure there are survival advantages for that, but at the same time people are generally much healthier on CR, and need less sleep. I feel that if you take a person who is sleeping 10 hours a day, and LIMIT their sleep, they will do not only worse off on an a day to day basis, but you could potentially cause them problem with immune systems, depression, fatigue and ultimately shorter life span.

Bottom line, have as much sleep as your body signals it needs.

[Live Forever]

The problem with studies like this that they show correlations not causations. To say that people (not in a lab under controlled conditions their whole life) who sleep 6.5-7.5 hours a night live longer than those that sleep less than 6.5 and more than 8 doesn't really mean anything. I am not going to write a lecture on statistics 101 in one post but this is a common mistake among people trying to interpret studies. Basically there may be other reasons why these people end up sleeping 6.5-7.5 hrs, maybe these are the productive healthy individuals who because of work and family obligation can only get this amount, thus they are preselected as high functioning possibly genetically above average people. Those who sleep more than 8 hours may be underemployed, have long standing illnesses, chronic fatigue, depression or other issues that make it necessary to sleep more and thus recover more, and they will live shorter lives because of these other problems.

What if we took the 6.5-7.5 hour preselected sleeping group and made them sleep 9 hours, would they live even longer, my thought is maybe so, would they live shorter lives, probably not. There is evidence to suggest that more sleep leads to better hormone profiles more repair of tissues etc. which is why people in distressed conditions naturally sleep more, there bodies are trying to get these benefits so that they can get out of the imbalanced state.

Then there is the whole bias in reporting, self reporting of sleep habits, eating habits etc. are notoriously inaccurate.

I agree. I basically said the same thing in the intro, (saying it isn't known if it is a cause or effect) and say the same thing in a lot of "religious studies" debates that I get into. Whether it is the cause, or the effect though, it is still interesting. The further study to determine which it is that they talked about for the future should provide more light on the situation.

[Live Forever]

Agree with Edward totally. I'm surprised the researchers have not mentioned this. In my opinion this is a very likely, and very plausible reason for the different requirements in sleep. You hear all the time how people go on CR need less sleep. Sure there are survival advantages for that, but at the same time people are generally much healthier on CR, and need less sleep. I feel that if you take a person who is sleeping 10 hours a day, and LIMIT their sleep, they will do not only worse off on an a day to day basis, but you could potentially cause them problem with immune systems, depression, fatigue and ultimately shorter life span.

Bottom line, have as much sleep as your body signals it needs.

If you listen to the audio, the main researcher guy basically says the same thing. (in different words, and doesn't mention CR of course)

[VictorBjoerk]

If a person has a great sleep requirement of 10-11 hours or so,doesn't that indicate that they are in general bad physical shape?

[spacetime]

How is sleep requirement even determined? Is it assumed that the duration one sleeps before naturally awaking is the requirement? I know some say the duration of certain sleep states is far more important but this is impractical to measure for most.

[VictorBjoerk]

Sleep requirement is certainly affected by light since people on northern latitudes require less sleep during the summer months,especially in the arctic....It is estimated that the sleep requirements is 2 hours or so less in the summer than in the winter and apparently without side effects...

[Luna]

I usually (naturally) only sleep 6.5-7.5 hours.. (don't feel tired when waking up.. hell barely feel tired when going to sleep if at all).
I wonder what does that mean

[Matt]

If a person has a great sleep requirement of 10-11 hours or so,doesn't that indicate that they are in general bad physical shape?

I was in bad shape after cipro for many months, and yes my sleeping requirement increased dramatically. Sleeping less than 11-12 hours a night made me feel bad. Now I have largely recovered I sleep about 8 hours on average.

[Ghostrider]

I think the optimal amount of sleep involves going to bed and waking up naturally without an alarm clock. Different people require different amounts of sleep.

[Mind]

Sleep helps people learn complicated tasks.

Using a test that involved learning to play video games, researchers showed for the first time that people who had "forgotten" how to perform a complex task 12 hours after training found that those abilities were restored after a night's sleep.

"Sleep consolidated learning by restoring what was lost over the course of a day following training and by protecting what was learned against subsequent loss," said Howard Nusbaum, Professor of Psychology at the University of Chicago, and a researcher in the study. "These findings suggest that sleep has an important role in learning generalized skills in stabilizing and protecting memory."

The results demonstrate that this consolidation may help in learning language processes such as reading and writing as well as eye-hand skills such as tennis, he said.

For the study, researchers tested about 200 college students, most of whom were women, who had little previous experience playing video games. The team reported the findings in the paper, "Consolidation of Sensorimotor Learning During Sleep," in the current issue of Learning and Memory. Joining Nusbaum in the research were lead author Timothy Brawn, a graduate student in Psychology at the University; Kimberly Fenn, now an Assistant Professor of Psychology at Michigan State University; and Daniel Margoliash, Professor in the Departments of Organismal Biology & Anatomy and Psychology at the University.

[Mind]

Lack of sleep may increase cancer risk.

Seems this study confirms the general rule of thumb (not absolute) that 7 to 9 hours of sleep is best for health.

The study involving 5,968 women in Maryland confirmed previous findings that people who do regular physical activity are less likely to develop cancer.

But when the researchers looked at the women ages 18 to 65 who were in the upper half in terms of the amount of physical exercise they got per week, they found that sleep appeared to play an important role in cancer risk.

Those who slept less than seven hours nightly had a 47 percent higher risk of cancer than those who got more sleep among the physically active women, the researchers reported at a meeting of the American Association for Cancer Research.

"We think it's quite interesting and intriguing. It's kind of a first look into this. It isn't something that has been widely studied," James McClain of the National Cancer Institute, part of the U.S. government's National Institutes of Health, said in a telephone interview.

McClain, who led the study, said it is unclear exactly how getting too little sleep may make one more susceptible to cancer. "Getting adequate sleep has been long associated with health," McClain said.

[Heliotrope]

I usually (naturally) only sleep 6.5-7.5 hours.. (don't feel tired when waking up.. hell barely feel tired when going to sleep if at all).
I wonder what does that mean

it means you're lucky. how do ppl naturally only sleep 3-4 hr a night, need only half as much as others

[Matt]

Maybe the increased risk of cancer has to do with a decline in immune function with lack of sleep?

[John_Ventureville]

I had a friend who was an Army officer and he told me that military researchers had determined as a general rule of thumb that to be able to lead troops and make wise decisions, a minimum of six hours of quality sleep was necessary.

John

[wydell]

There are studies that seem to indicate that too much and too little sleep are harmful. The studies that I recall reading seemed to suggest that 6-7 hours is optimal.

[wydell]

There are studies that seem to indicate that too much and too little sleep are harmful. The studies that I recall reading seemed to suggest that 6-7 hours is optimal.

[Putz]

My friend in a course called "Introduction to Sleep" said the optimum stated by the professor and and the textbook (Based on the average of statistics on tests for optimum mental performance following various sleep lengths) is 8.4 hours, 8 hours and 24 minutes. However, optimum sleep levels for mental rest and performance may not exactly correlate to sleep levels for long term bodily health. I've heard that chronic lack of sleep has semi-permanent adverse effects and that it has no permanent effects, from various people.

Just try to get around 8 hours of sleep as often as possible, I say. Unfortunately because of college life I'm not following that rule of thumb as often as I would like to.

[Heliotrope]

i seemed to make up too much sleep in thanksgiving break. i hate the yo-yo type , like yo-yo diet , extremes. I need help with sleep probs. Now I've got early class and need to work.

i think ppl should be able to fxn well on 6 hrs for very long term

[Mind]

Proper sleeps helps ward off colds.

Prior research has suggested that sleep boosts the immune system at the cell level. This is the first study to show small sleep disturbances increasing the risk of getting sick, said Dr. Michael Irwin, who researches immune response at the University of California, Los Angeles, and was not involved in the study.

"The message is to maintain regular sleep habits because those are really critical for health," Irwin said.

Up against the virus
During cold season, staying out of range of sneezing relatives and co-workers may be impossible. The study, appearing Monday in the Archives of Internal Medicine, mimicked those conditions by exposing participants to a common cold virus — rhinovirus — and most became infected with it.

But not everyone suffered cold symptoms.

The people who slept less than seven hours a night in the weeks before they were exposed to the virus were three times more likely to catch a cold than those who slept eight hours or more.

[JLL]

They say we sleep one third of our life. Therefore, sleeping more must increase lifespan.

[FunkOdyssey]

"Sleep Habits and Susceptibility to the Common Cold"
by
Sheldon Cohen, Ph.D.; William J. Doyle, Ph.D.; Cuneyt M. Alper,
M.D.; Denise Janicki-Deverts, Ph.D.;
and Ronald B. Turner, M.D.
Archives of Internal Medicine, Vol. 169, No. 1, pp. 62-7 (January 12, 2009).


Background: Sleep quality is thought to be an important predictor of immunity and, in turn, susceptibility to the common cold. This article examines whether sleep duration and efficiency in the weeks preceding viral exposure are associated with cold susceptibility.

Methods: A total of 153 healthy men and women (age range, [21 - 55] years) volunteered to participate in the study. For 14 consecutive days, they reported their sleep duration and sleep efficiency (percentage of time in bed actually asleep) for the previous night and whether they felt rested. Average scores for each sleep variable were calculated over the 14-day baseline. Subsequently, participants were quarantined, administered nasal drops containing a rhinovirus, and monitored for the development of a clinical cold (infection in the presence of objective signs of illness) on the day before and for five days after exposure.

Results: There was a graded association with average sleep duration: participants with less than seven hours of sleep were 2.94 times (95% confidence interval [CI: 1.18-7.30]) more likely to develop a cold than those with eight hours or more of sleep. The association with sleep efficiency was also graded: participants with less than 92% efficiency were 5.50 times (95% [CI: 2.08-14.48]) more likely to develop a cold than those with 98% or more efficiency. These relationships could not be explained by differences in prechallenge virus-specific antibody titers, demographics, season of the year, body mass, socioeconomic status, psychological variables, or health practices. The percentage of days feeling rested was not associated with colds.

Conclusion: Poorer sleep efficiency and shorter sleep duration in the weeks preceding exposure to a rhinovirus were associated with lower resistance to illness.

[Matt]

In december it was the first time I caught the flu or a cold in 2 years, I was sleep deprived for about 5 days, very tired! (because of noisy people!). I thought to myself when it happened it probably was the fact I got so little sleep during that time (maybe that was right). I do wonder if it possible to attenuate some of the negative impacts on immunity with certain supplements

Edited by Matt, 14 January 2009 - 05:20 PM.