What is it exactly about a late sleep cycle that causes it to be unhealthy?
May 20, 2011 2:45 AM Subscribe
What is it exactly about a late sleep cycle that causes it to be unhealthy?
I'm a very late sleeper and friends/family are always sending me articles about all the unhealthy aspects of a late sleep cycle. The reasons range from it messing up your hormones and natural cycles to your maximum healing happening in certain hours. But assuming you are getting a healthy full ~8 hour sleep and are consistent in your sleep/wake time, what causes it to be unhealthy? Isn't the body's internal clock relative, not absolute, and all your natural hormone and circadian rhythms would adjust to whatever cycle you are on?
I'm a very late sleeper and friends/family are always sending me articles about all the unhealthy aspects of a late sleep cycle. The reasons range from it messing up your hormones and natural cycles to your maximum healing happening in certain hours. But assuming you are getting a healthy full ~8 hour sleep and are consistent in your sleep/wake time, what causes it to be unhealthy? Isn't the body's internal clock relative, not absolute, and all your natural hormone and circadian rhythms would adjust to whatever cycle you are on?
If I recall correctly, it's shift work, not having a naturally late sleep cycle which causes problems. Some people have a genetic tendency to sleep later and I cannot recall seeing any evidence that natural 'owls' with later chronotypes have health risks. Also if you are a young person in your twenties or earlier, you may still have the natural later shift which begins at puberty - which due to timing of hormone release means that teenagers naturally go to bed later and get up later. Historically because the business world took on the early rising habits of the agricultural world there is a social bias against 'owls' and against the temporary shift to 'owlishness' which teenagers/young adults have. This makes 'owls' a tempting target for a moralistic spin on sleep science stories which often leads to the science being distorted to make a false 'early rising is better' point.
If you want to get the science behind it try this blogpost by Coturnix and this one on young adult sleep schedules. His blog is the best place to check out the science, as your family may be sending you popular articles which don't get the science right, and which may be unnecessarily alarming you. Maybe you should send them some of his blog posts :-)
posted by Flitcraft at 3:19 AM on May 20, 2011 [26 favorites]
If you want to get the science behind it try this blogpost by Coturnix and this one on young adult sleep schedules. His blog is the best place to check out the science, as your family may be sending you popular articles which don't get the science right, and which may be unnecessarily alarming you. Maybe you should send them some of his blog posts :-)
posted by Flitcraft at 3:19 AM on May 20, 2011 [26 favorites]
I've also heard that some of the problem is from your days off, when you are up during daylight and sleep during night-time because you're usually not able to live a fully-nocturnal lifestyle with family and friends who are on a traditional sleep schedule.
posted by autoclavicle at 3:23 AM on May 20, 2011
posted by autoclavicle at 3:23 AM on May 20, 2011
hello, fellow night owl. I have been living the late lifestyle, and I've read that as long as your shedule is regular, and you get enough sleep, it's totally fine.
DSPS
I get waaaaaay better sleep since I was able to work full time night shift, and embrace my owlish nature. If I have to get up mornings, I get a terrible sleep, very unhealthy.
posted by 5_13_23_42_69_666 at 4:06 AM on May 20, 2011
DSPS
I get waaaaaay better sleep since I was able to work full time night shift, and embrace my owlish nature. If I have to get up mornings, I get a terrible sleep, very unhealthy.
posted by 5_13_23_42_69_666 at 4:06 AM on May 20, 2011
Some people have a genetic tendency to sleep later
Other way around. Some people have a genetic tendency to sleep less. (REF)
posted by kisch mokusch at 5:10 AM on May 20, 2011
Other way around. Some people have a genetic tendency to sleep less. (REF)
posted by kisch mokusch at 5:10 AM on May 20, 2011
I get as much done between the hours of 9PM - midnight+ as anybody could get done between 4AM - 7Am.
What problems and health issues are you experiencing?
posted by buzzman at 5:25 AM on May 20, 2011
What problems and health issues are you experiencing?
posted by buzzman at 5:25 AM on May 20, 2011
I'm not sure sleeping later and sleeping less are opposite, kish mokusch. You can sleep five hours, but if those five hours are between 5am and 10am, that's sleeping "late."
My natural sleep cycle - and I will be 32 this year - has been midnight to 8am for as long as I can remember. I am currently working from home and for the first time ever, I can sleep the way I like, and I feel like a million dollars. I feel BETTER.
Screw 5am. I'll get up that early when it makes me feel as good as sleeping til 8. I think as long as you feel fine, you're fine.
posted by Medieval Maven at 5:51 AM on May 20, 2011 [1 favorite]
My natural sleep cycle - and I will be 32 this year - has been midnight to 8am for as long as I can remember. I am currently working from home and for the first time ever, I can sleep the way I like, and I feel like a million dollars. I feel BETTER.
Screw 5am. I'll get up that early when it makes me feel as good as sleeping til 8. I think as long as you feel fine, you're fine.
posted by Medieval Maven at 5:51 AM on May 20, 2011 [1 favorite]
Do you feel fine? Are you able to get adequate sleep (not forced to get up early)? Then it's fine. The age-related sleep shift thing is no joke, though. I had a stunning switch from being a night owl to being an (involuntary) early bird. Now that I'm on the other side of it, I can easily see how people might get confused. They assume that if sleeping one way is right for them now then it must always have been the right way.
(If you really want to shake them up? Tell them the idea of sleeping all night was made up by mattress and sleep drug companies and is weird and unnatural and probably suboptimal.)
posted by anaelith at 5:54 AM on May 20, 2011
(If you really want to shake them up? Tell them the idea of sleeping all night was made up by mattress and sleep drug companies and is weird and unnatural and probably suboptimal.)
posted by anaelith at 5:54 AM on May 20, 2011
What's bad about being a late sleeper is that the world makes you get up at the crack of dawn to go to work, and thus you will spend your entire working life not getting enough sleep because you have to get up at 6 a.m. to go to work. And thus every "wah, humans don't get enough sleep and then bad things happen to your health" story applies to you. Unfortunately, naturally turning yourself into an early bird just doesn't really work too well, so...
Yeah, you're gonna get nagged forever and there's nothing you can do about it.
But if the world didn't run on an early bird schedule and you could sleep as you like? No, there would be no harm done to you whatsoever.
posted by jenfullmoon at 5:55 AM on May 20, 2011 [1 favorite]
Yeah, you're gonna get nagged forever and there's nothing you can do about it.
But if the world didn't run on an early bird schedule and you could sleep as you like? No, there would be no harm done to you whatsoever.
posted by jenfullmoon at 5:55 AM on May 20, 2011 [1 favorite]
kisch mokusch Other way around. Some people have a genetic tendency to sleep less.
Either/both, isn't it? Flitcraft had the right idea.
If you have delayed sleep phase disorder (DSPS) but have to rise and work by normal business hours, chances are you suffer from some degree of chronic sleep deprivation, which is known to be harmful.
lollusc is right that even late sleepers' bodies get cues from light. In that sense, the body's internal clock isn't relative unless you are wholly deprived of light cues. Some blind people take melatonin daily to entrain their body clocks. http://www.nytimes.com/1999/06/22/health/melatonin-used-to-restore-sleep-patterns-in-blind-people.html Night shift work is classified as a carcinogen due to the exposure to light. http://www.washingtonpost.com/wp-dyn/content/article/2008/02/19/AR2008021902398.html
Most night owls and people with DSPS don't avoid daylight hours entirely and I haven't heard that night owlism is associated with health problems absent a struggle against working world hours. It may be, but if you are a hardcore night owl or have DSPS, the amount of fighting your body that you have to do to maintain a standard working world schedule is probably worse for you than maintaining a consistent sleep schedule.
That said, there are a lot of people since easy night lighting and electronics showed up who stay awake beyond what they would have if they were born five thousand years ago. It's not wise to delude yourself into thinking you can/should sleep like a night owl if without your laptop or phone you can go to sleep at 10:00 or 11:00 pm.
posted by hat at 6:26 AM on May 20, 2011
Either/both, isn't it? Flitcraft had the right idea.
If you have delayed sleep phase disorder (DSPS) but have to rise and work by normal business hours, chances are you suffer from some degree of chronic sleep deprivation, which is known to be harmful.
lollusc is right that even late sleepers' bodies get cues from light. In that sense, the body's internal clock isn't relative unless you are wholly deprived of light cues. Some blind people take melatonin daily to entrain their body clocks. http://www.nytimes.com/1999/06/22/health/melatonin-used-to-restore-sleep-patterns-in-blind-people.html Night shift work is classified as a carcinogen due to the exposure to light. http://www.washingtonpost.com/wp-dyn/content/article/2008/02/19/AR2008021902398.html
Most night owls and people with DSPS don't avoid daylight hours entirely and I haven't heard that night owlism is associated with health problems absent a struggle against working world hours. It may be, but if you are a hardcore night owl or have DSPS, the amount of fighting your body that you have to do to maintain a standard working world schedule is probably worse for you than maintaining a consistent sleep schedule.
That said, there are a lot of people since easy night lighting and electronics showed up who stay awake beyond what they would have if they were born five thousand years ago. It's not wise to delude yourself into thinking you can/should sleep like a night owl if without your laptop or phone you can go to sleep at 10:00 or 11:00 pm.
posted by hat at 6:26 AM on May 20, 2011
I went to a lecture by John Medina last year, during which he said if you're an owl you're an owl (and if you're a lark you're a lark) and there's nothing you can do about it.
posted by The corpse in the library at 6:41 AM on May 20, 2011
posted by The corpse in the library at 6:41 AM on May 20, 2011
I am an owl. Getting up early in the morning gives me headaches and makes me feel like shit, regardless of when I went to bed and how much sleep I had. It messes me up.
I take this as a sign that its not good for me to try force myself into a different sleep schdule "just because", and everything I've read indicates that you'll be fine as long as you have a routine and are actually getting enough sleep.
And yes, the human body clock is relative.
posted by stillnocturnal at 7:13 AM on May 20, 2011
I take this as a sign that its not good for me to try force myself into a different sleep schdule "just because", and everything I've read indicates that you'll be fine as long as you have a routine and are actually getting enough sleep.
And yes, the human body clock is relative.
posted by stillnocturnal at 7:13 AM on May 20, 2011
My family has, for several generations now, been full of extreme owls. My preferred sleep schedule is 2 am to 10 am, and both my kids are the same way. In the summer, when we can sleep when we want to, we all feel great.
However, we also have high rates of obesity and diabetes. I read that sleep issues could exacerbate both of these tendencies, so I asked my doctor about it. She said that it was likely that the extreme owls in my family were probably trying to force themselves into an earlier schedule, and thereby not getting enough sleep. She said it doesn't necessarily matter when you sleep, as long as you're getting enough.
When I talked to my mom (age 62) and my great aunt (age 76) they both said they had spent their lives getting 4 to 6 hours of sleep at night because they had to get up early for work. They're both retired and have reverted completely to the 2 to 10 schedule.
posted by SamanthaK at 7:43 AM on May 20, 2011
However, we also have high rates of obesity and diabetes. I read that sleep issues could exacerbate both of these tendencies, so I asked my doctor about it. She said that it was likely that the extreme owls in my family were probably trying to force themselves into an earlier schedule, and thereby not getting enough sleep. She said it doesn't necessarily matter when you sleep, as long as you're getting enough.
When I talked to my mom (age 62) and my great aunt (age 76) they both said they had spent their lives getting 4 to 6 hours of sleep at night because they had to get up early for work. They're both retired and have reverted completely to the 2 to 10 schedule.
posted by SamanthaK at 7:43 AM on May 20, 2011
I think it's really nice that you are sincerely trying to understand this. If you are getting adequate sleep, and your sleep cycle isn't interfering with work, play, etc., than I'll answer a different question.
How can you most effectively respond to people who don't like your sleep cycle? Be super cheerful, and find the parts of the article that support you; agree enthusiastically. "Thanks for the article, Jane, it helps explain why you are so chipper in the morning. I totally agree that getting a sold 8 hours makes a big difference. " "Mom, that article's interesting. It supports getting enough sleep; that's why I sleep till 10 - I go to bed at 2!" People really do care about you, but many larks insist that everyone must be a lark. The owls I know are perfectly happy to be up alone at midnight; it's quiet, calm, and the stars are beautiful.
posted by theora55 at 10:02 AM on May 20, 2011
How can you most effectively respond to people who don't like your sleep cycle? Be super cheerful, and find the parts of the article that support you; agree enthusiastically. "Thanks for the article, Jane, it helps explain why you are so chipper in the morning. I totally agree that getting a sold 8 hours makes a big difference. " "Mom, that article's interesting. It supports getting enough sleep; that's why I sleep till 10 - I go to bed at 2!" People really do care about you, but many larks insist that everyone must be a lark. The owls I know are perfectly happy to be up alone at midnight; it's quiet, calm, and the stars are beautiful.
posted by theora55 at 10:02 AM on May 20, 2011
Melatonin production relies on simultaneously (1) it's dark where you are, plus (2) you're trying, and generally succeeding, to sleep.
If you don't produce melatonin (because, for example, you're trying to sleep with the lights on, or you're sitting in bed reading brightly lit Wikipedia and waiting to feel sleepy) then you won't sleep very well.
If you're asleep and producing melatonin, then production ramps down when it starts to get light and/or in about 8 hours. If you don't get some nice bright (brighter than the average office) light in your eyes over the next 8 hours after you get up, then your cycle doesn't want to reset. The average body-clock runs about 24.5 hours. A lack of a cycle reset means it's harder to then get to sleep when you want to, and/or get up when you want to or when the alarm tells you to, and/or interrupted less restful sleep. It's that lack of sleep that contributes to bad health and cancer and all sorts of epidemiological study drama.
There's some evidence that blue light is particularly strong at supressing melatonin production - which you want to do during the daytime (because it's the swings in melatonin level that produce healthy sleep/wake cycles) and avoid at night because you're about to want all the melatonin production you can get.
So, that amount of light is equivalent to looking at the sky for 25 minutes, looking at the ground outside for 35-40 minutes, looking directly at an overhead fluorescent tube fixture for ~2 hours - and looking at a surface illuminated by an overhead fluorescent tube fixture won't work in a 16-hour day, the plot of time vs lux swoops up dramatically. The plot I'm thinking of doesn't address the blueness of the light, so I'm not sure where the average computer monitor showing text on a white background fits in to that scheme.
You might find some of this lighting research interesting, even though the website won't show me the plot that was in a presentation I saw from there.
So, you ought to be okay...
If you haven't got morning alarms that push you into getting less than 8 hours sleep.
If your schedule is pretty consistent and isn't getting shifted back and forth.
If your sleeping space is dark for the entire time you're trying to sleep in it (which may mean blackout curtains for morning sunshine).
If you're not getting a lot of light (especially blue light, such as from computers) right before you go to bed.
If you're getting at least 30 minutes of bright (and/or blue) light at some point during the 16 hours that you're awake, preferably toward the beginning.
posted by aimedwander at 11:55 AM on May 20, 2011 [1 favorite]
If you don't produce melatonin (because, for example, you're trying to sleep with the lights on, or you're sitting in bed reading brightly lit Wikipedia and waiting to feel sleepy) then you won't sleep very well.
If you're asleep and producing melatonin, then production ramps down when it starts to get light and/or in about 8 hours. If you don't get some nice bright (brighter than the average office) light in your eyes over the next 8 hours after you get up, then your cycle doesn't want to reset. The average body-clock runs about 24.5 hours. A lack of a cycle reset means it's harder to then get to sleep when you want to, and/or get up when you want to or when the alarm tells you to, and/or interrupted less restful sleep. It's that lack of sleep that contributes to bad health and cancer and all sorts of epidemiological study drama.
There's some evidence that blue light is particularly strong at supressing melatonin production - which you want to do during the daytime (because it's the swings in melatonin level that produce healthy sleep/wake cycles) and avoid at night because you're about to want all the melatonin production you can get.
So, that amount of light is equivalent to looking at the sky for 25 minutes, looking at the ground outside for 35-40 minutes, looking directly at an overhead fluorescent tube fixture for ~2 hours - and looking at a surface illuminated by an overhead fluorescent tube fixture won't work in a 16-hour day, the plot of time vs lux swoops up dramatically. The plot I'm thinking of doesn't address the blueness of the light, so I'm not sure where the average computer monitor showing text on a white background fits in to that scheme.
You might find some of this lighting research interesting, even though the website won't show me the plot that was in a presentation I saw from there.
So, you ought to be okay...
If you haven't got morning alarms that push you into getting less than 8 hours sleep.
If your schedule is pretty consistent and isn't getting shifted back and forth.
If your sleeping space is dark for the entire time you're trying to sleep in it (which may mean blackout curtains for morning sunshine).
If you're not getting a lot of light (especially blue light, such as from computers) right before you go to bed.
If you're getting at least 30 minutes of bright (and/or blue) light at some point during the 16 hours that you're awake, preferably toward the beginning.
posted by aimedwander at 11:55 AM on May 20, 2011 [1 favorite]
This thread is closed to new comments.
posted by lollusc at 3:14 AM on May 20, 2011