# Bodily functions during sleep **URL:** \ **Category:** Factual Questions\ **Created:** [May 28, 2017, 1:01am UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572 "2017-05-28T01:01:03Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Warm\_blood](https://avatars.discourse-cdn.com/v4/letter/w/df705f/32.png) [@Warm\_blood](https://boards.straightdope.com/u/Warm_blood)\ **Post date:** [May 28, 2017, 1:01am UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/1 "2017-05-28T01:01:03Z")
I’m battling a cold right now. Runny nose and cough. How is it that when I sleep my nose stops running and my cough ceases but the moment I wake up all of those symptoms restart? Since those aren’t normal bodily functions, how does my body know when to start and stop them? ---
**Author:** ![ASGuy](https://avatars.discourse-cdn.com/v4/letter/a/838e76/32.png) [@ASGuy](https://boards.straightdope.com/u/ASGuy)\ **Post date:** [May 28, 2017, 1:49am UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/2 "2017-05-28T01:49:50Z")
This is a question I have pondered occasionally. I am not a neuro-anything but the brain can do amazing things if it wants to. Witness its ability to shut off muscular action when sleeping. I would venture that the answer is as simple as the brain saying to itself “I need sleep more than I need a runny nose or coughing, so no more runny nose or coughing.” ---
**Author:** ![snfaulkner](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snfaulkner/32/433_2.png) [@snfaulkner](https://boards.straightdope.com/u/snfaulkner)\ **Post date:** [May 28, 2017, 1:52am UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/3 "2017-05-28T01:52:42Z")
I dunno that it \*does \*stop when sleeping. I’ve often woken myself up coughing. Or woken up to find that my runny nose is either all over the pillow, or down my throat, choking me. ---
**Author:** ![Ambivalid](https://avatars.discourse-cdn.com/v4/letter/a/a5b964/32.png) [@Ambivalid](https://boards.straightdope.com/u/Ambivalid)\ **Post date:** [May 28, 2017, 2:41am UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/4 "2017-05-28T02:41:33Z")
I’ve had severe bronchitis before and the coughing did _not_ stop, no matter what. If I did manage to get to sleep, I would quickly be woken up by fits of coughing. It was absolute agony. ---
**Author:** ![Heracles](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/heracles/32/487_2.png) [@Heracles](https://boards.straightdope.com/u/Heracles)\ **Post date:** [May 28, 2017, 5:18am UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/5 "2017-05-28T05:18:16Z")
I think the runny nose works differently when you’re lying on your back (the mucus just flows down into your throat). ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [May 28, 2017, 12:55pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/6 "2017-05-28T12:55:25Z")
> [@Heracles](#): > > I think the runny nose works differently when you’re lying on your back (the mucus just flows down into your throat). I have never slept on my back, but I have the same experience. ---
**Author:** ![StarvingButStrong](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/starvingbutstrong/32/335_2.png) [@StarvingButStrong](https://boards.straightdope.com/u/StarvingButStrong)\ **Post date:** [May 28, 2017, 2:30pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/7 "2017-05-28T14:30:43Z")
I think the point of coughing is to clear something obstructing your breathing. And if you can’t breathe, you die. So I really doubt your brain will completely turn off coughing for hours on end. But maybe it changes the threshold for when a bout of coughing starts? Like even a 2% reduction in getting air in is enough to make you cough while awake, but your brain/body will ignore that until it rises to 10% when you’re sleeping? ---
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [May 28, 2017, 3:20pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/8 "2017-05-28T15:20:37Z")
> [@Ambivalid](#): > > I’ve had severe bronchitis before and the coughing did _not_ stop, no matter what. If I did manage to get to sleep, I would quickly be woken up by fits of coughing. It was absolute agony. Hey, me too! QFT ---
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [May 28, 2017, 3:21pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/9 "2017-05-28T15:21:40Z")
> [@Hari\_Seldon](#): > > I have never slept on my back… :dubious: but interested. ---
**Author:** ![Patx2](https://avatars.discourse-cdn.com/v4/letter/p/73ab20/32.png) [@Patx2](https://boards.straightdope.com/u/Patx2)\ **Post date:** [May 28, 2017, 3:55pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/10 "2017-05-28T15:55:12Z")
> [@Heracles](#): > > I think the runny nose works differently when you’re lying on your back (the mucus just flows down into your throat). I find if I do that when I have a cold though, it causes me to wake up coughing. ---
**Author:** ![Thudlow\_Boink](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thudlow_boink/32/320_2.png) [@Thudlow\_Boink](https://boards.straightdope.com/u/Thudlow_Boink)\ **Post date:** [May 28, 2017, 3:58pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/11 "2017-05-28T15:58:02Z")
> [@Warm\_blood](#): > > Ibut the moment I wake up all of those symptoms restart Is it possible you have the causation the wrong way around? (i.e. you wake up because the symptoms restart, instead of the symptoms restarting because you wake up) ---
**Author:** ![ThelmaLou](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thelmalou/32/390_2.png) [@ThelmaLou](https://boards.straightdope.com/u/ThelmaLou)\ **Post date:** [May 28, 2017, 4:05pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/12 "2017-05-28T16:05:11Z")
> [@Hari\_Seldon](#): > > I have never slept on my back, but I have the same experience. > [@Leo\_Bloom](#): > > :dubious: but interested. I never sleep on my back either. Okay, I did for a few weeks 10 years ago when my leg was in a cast. Otherwise, never. If I have a cough, lying down aggravates it. I use a [wedge pillow](https://www.bedbathandbeyond.com/store/product/bedding-essentials-trade-bed-wedge-pillow/3272639?Keyword=10060850) (or just make a pillow mountain/ramp) to elevate my upper body at least 10-15 degrees. That helps with the coughing. My nose definitely runs when I’m asleep. When I was a kid, I’d wake up with this Mississippi delta of nose effluent encrusted around my nostrils and upper lip and my mother would bring me a damp wash cloth to soften it. (Sorry, TMI). ---
**Author:** ![ENugent](https://avatars.discourse-cdn.com/v4/letter/e/4af34b/32.png) [@ENugent](https://boards.straightdope.com/u/ENugent)\ **Post date:** [May 28, 2017, 4:23pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/13 "2017-05-28T16:23:40Z")
I cannot sleep on my back, either. Even when I was eight months pregnant, I slept on my side with my body twisted as close to stomach-down as it could get. Rolling me onto my back invariably wakes me up. ---
**Author:** ![Warm\_blood](https://avatars.discourse-cdn.com/v4/letter/w/df705f/32.png) [@Warm\_blood](https://boards.straightdope.com/u/Warm_blood)\ **Post date:** [May 28, 2017, 4:55pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/14 "2017-05-28T16:55:30Z")
> [@Thudlow\_Boink](#): > > Is it possible you have the causation the wrong way around? (i.e. you wake up because the symptoms restart, instead of the symptoms restarting because you wake up) No, I really do wake up without my sleep being interrupted feeling dandy for a glorious few minutes and then my cough kicks in. My nose starts running again a little after, usually after washing my face (no, the water does not seep into my nostrils). And I hardly ever sleep on my back. I appear to be the only person like this because no one else can relate. :dubious: ---
**Author:** ![Shagnasty](https://avatars.discourse-cdn.com/v4/letter/s/9dc877/32.png) [@Shagnasty](https://boards.straightdope.com/u/Shagnasty)\ **Post date:** [May 28, 2017, 6:14pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/15 "2017-05-28T18:14:55Z")
This is a decent question and I suspect that no one in the world has the full answer because no one really understands why we sleep at all. It doesn’t make a lot of sense intuitively for mammals to have to lay or stand still for many hours a day at a stretch and yet you will get sick and eventually die if you skip sleep for even a few days. Researchers are working on it but nobody has figured it out yet. The thing I have always wondered is why you get woken up to pee but almost never to poop? Apparently my body thinks that a half-full bladder is an emergency that requires an immediate response but dropping off a large load can always wait until the next business day. Some brain functions and CNS functions are suppressed or shut down during sleep. That is about all you can say at this point. ---
**Author:** ![Weisshund](https://avatars.discourse-cdn.com/v4/letter/w/ba8739/32.png) [@Weisshund](https://boards.straightdope.com/u/Weisshund)\ **Post date:** [May 28, 2017, 7:04pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/16 "2017-05-28T19:04:58Z")
> [@Shagnasty](#): > > The thing I have always wondered is why you get woken up to pee but almost never to poop? Apparently my body thinks that a half-full bladder is an emergency that requires an immediate response but dropping off a large load can always wait until the next business day. > > Some brain functions and CNS functions are suppressed or shut down during sleep. That is about all you can say at this point. For me coughing does not cease at sleep, in interrupts sleep, running nose continues to run, which ever direction gravity dictates. Peeing? sometimes the need to pee will wake me up, but i generally forgive Mr Bladder because when he does this, it’s usually because he is toting around the approximation of a 2 liter bottle full, poor guy is about to bust. As for the solid waste disposal facilities, that depends on what kind of day they are having. If i have done something dumb like Oh say eating a bunch of hot peppers, or there has been some kind of disagreement among the resident flora, there will indeed be an emergency evacuation alarm going off at some point during the night. I will of course ignore it up until the point it becomes “Battle Stations, all hands on deck!!” Then there is no ignoring it. ---
**Author:** ![Patch](https://avatars.discourse-cdn.com/v4/letter/p/a183cd/32.png) [@Patch](https://boards.straightdope.com/u/Patch)\ **Post date:** [May 29, 2017, 7:48pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/17 "2017-05-29T19:48:02Z")
> [@snfaulkner](#): > > I dunno that it \*does \*stop when sleeping. I’ve often woken myself up coughing. Or woken up to find that my runny nose is either all over the pillow, or down my throat, choking me. This. I’ve slept with towels over my pillow when I’ve had bad colds to deal with this issue. ---
**Author:** ![Grrr](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/grrr/32/146_2.png) [@Grrr](https://boards.straightdope.com/u/Grrr)\ **Post date:** [May 29, 2017, 8:10pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/18 "2017-05-29T20:10:14Z")
I thought it was because when you are asleep, you remain relatively still, and all the crap in your lungs settles to one side reducing the irritation to your lungs. When you wake up, you start to move around which restarts the irritation in your lungs. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [May 29, 2017, 10:06pm UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/19 "2017-05-29T22:06:13Z")
> [@Shagnasty](#): > > The thing I have always wondered is why you get woken up to pee but almost never to poop? Apparently my body thinks that a half-full bladder is an emergency that requires an immediate response but dropping off a large load can always wait until the next business day. This is most definitely NOT true when you are suffering from diarrhea, like during an illness or during a course of antibiotics. But then, people can often wait for several hours during a work day without a bowel movement. It just isn’t usually that urgent. ---
**Author:** ![GusNSpot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gusnspot/32/436_2.png) [@GusNSpot](https://boards.straightdope.com/u/GusNSpot)\ **Post date:** [May 30, 2017, 2:03am UTC](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572/20 "2017-05-30T02:03:10Z")
I did not know there were two sphincter muscles. TMI … The one major one at the end of the line is broken in me. Every stomach growl or sensation is an emergency for me. Blows to be me. [Next page](https://boards.straightdope.com/t/bodily-functions-during-sleep/787572.md?page=2)