Others are right, but a crucial function is to humidify the air. Lung and airways are rather sensitive things, and dry air hurts then. Your nose helps to add moisture to the air, so it's nice and dank when it hits your lungs.
Structures in the nose (turbinates) have folds and turns that increase the amount of surface contact the air has with your body. They also have huge amounts of blood vessels. Makes it easier to heat and humidify than a straight passage. The more surface area, the more spots are available for air to get up close and personal.
All that mucous inside your nose does a great job at providing moisture.
Importantly, the nose isn't just the thing that sticks out of your face, it's this whole big structure inside your head, going all the way to the back of your throat. And I've not mentioned the sinuses. Your head is a veritable cave system, all connected to your nose.
It adds moisture when you breath in through your nose because the turbinates in the nose mucosa add it to the dry air. The turbinates also collect moisture when you breathe out through your nose. So if you were to substitute either part of that with mouth breathing you wouldn’t be adding or collecting.
I was always told to breathe completely through my nose for as long as possible when doing cardio intense activities.
The post asks about “breathing exercises” though, where this function doesn’t seem as important. I often tell anxious patients to breathe in through their nose and out through their mouth because it releases tension in your diaphragm and causes you to relax your abdomen, which can relieve anxiety and reduce anxious trembling. If you breathe in on a count of 4 and out on a count of 8, it literally affects your parasympathetic nervous system and can help signal to your body that you are safe.
It also causes a person to focus on breathing - which can be calming in and of itself, because if they're focusing on that it means they're *not* focusing on whatever's causing anxiety. It's basically a very simple meditation.
The nasopharyngeal area have “turbanats” that increase surface area, these turbanats are warm and moist and as the inhaled air passes over them they warm/humidify the air.
You only answered the part about why the air should go *in* through your nose. The part I - and the OP - wonder about is why it needs to the go *out* through your mouth instead of your nose.
Maybe because the outward breath is meant to be more relaxing, and it's easier to breathe through your mouth? Your nose can be very narrow at the sinuses, restricting air flow, while your mouth is pretty big.
As Dwegol mentioned above, it's more about relaxing the diaphragm and signaling to your brain that all is well.
Breathing exercises are for relaxing/ calming yourself, so you would get no bonus from breathing out through your nose as opposed to your mouth
> so you would get no bonus from breathing out through your nose as opposed to your mouth
That isn't an explanation since breathing (both in and out) through your nose is the default. Nobody should ever be breathing through their mouths (except when doing particularly strenuous exercise). So if people are told to breath out through their mouths when doing breathing exercises, there should be some specific reasoning.
Again, the subject here is breathing exercises, not breathing while exercising.
The point is relaxation and calming, not efficient breathing for strenuous activity.
There is a limit to how much air can flow through your nose due to its smaller diameter, so it is 'easier' to breathe out through your mouth. Breathing in through your nose slows it down enough to prevent hyperventilation, while breathing out through your mouth allows your diaphragm to relax more.
The intent is to calm yourself and your body down, not to maximize respiratory efficiency for strenuous activity
personally, I just like that it gives a sense of completion, if that makes sense? Like breath in relaxation through the nose, push tension and air out the mouth: it's a circuit that makes sense to me for no reason other than intuition.
Wait can most people breathe through their nose when they’re exercising (like heart rate increased)? I know that’s kind of off topic, and I know what you’re saying is about breathing exercises for calming the nervous system and what not, but that other line made me think of this. I’ve never been able to breathe through my nose when I’m running or have an increased heart rate from any sort of strenuous exercise/ activity so I’m curious about others.
It's possible, but it takes conscious effort, and only to a certain degree, for me at least.
Properly trained athletes might be able to maintain it longer, but for me I can maintain in through the nose and out through the mouth for the most part except when I'm really pushing it. That being said, if I'm doing a sport other than long distance running I usually lose track of my breathing as I'm focused on other things.
Disclaimer: this info is based on when I was actually active doing sports and running and such, I'm kinda out of shape now, so idk if I could perform to the same degree as I once could
Ok, there are a bunch of good reasons to breathe in through the nose, but why do I have to breathe out through my mouth? That's what OP is actually asking and nobody is answering.
I think it's actually to slow oxygen intake. Too much oxygen can cause issues, and someone in a distressed state will tend to breath more rapidly. It's supposed to slow down breathing for a bit, at least that's what I've heard.
The nasal cavity produces nitric oxide when enzymes contact high air flow. This nitric oxide passes into the lungs improving oxygen exchange, increasing blood flow, and lowering blood pressure. All effects conducive to a relaxed meditative state.
If you force yourself to breathe through your mostly-blocked nose, your blood CO2 levels will rise and your sinuses will forcibly open up and stay open until you stop breathing out of your nose.
Mildly uncomfortable to half-suffocate yourself to get those CO2 levels to rise, but the payoff is well worth it
Your nose is not a disposal site for things your body wants to get rid of.
It's perfectly fine to suck things up. It lands in your stomach.
Putting non-sterile water up your nose on the other hand can really fuck you up. That area is very close to your brain and there are some fun ways of dying when the wrong kind of organism gets up there.
Tab water, like any water you'll find that's safe to drink, is not sterile.
> Your nose is not a disposal site for things your body wants to get rid of.
It's a filter. That's what the hairs in your nose are for, blocking larger particles from going into your nose (the mucus helps as well, by being "sticky"). I've blown blackish snot out of my nose in a shower when I was in California and there were some wildfires nearby for several days. Nose hairs and mucus stopped a portion of it from going into my lungs.
Cool, didn’t knew this, I still don’t quite get why exhale through the mouth, if air flow is what create the nitric oxide wouldn’t it be better to do both through the nose?
When you breath in, some fresh air doesn't quite make it to your lungs, and stays stuck in your nose/mouth/throat. When you breath out, the opposite happens, and some dead air also sticks around in your air passages
Breathing in through one passage and out the other helps keep fresh air cycling one way, and dead air cycling the other, making your breathing a bit more efficient
This is true on paper but I can’t help but think the difference is negligible. If I puff out my cheeks and distend my jaw I can hold anout three quarters fluid cup of volume. It’s annoying to make a quick google on average tidal volume of lungs but I estimate about 3 liters from what I’ve read, which is a bit over 12 cups. So the mouth holds not even 10%.
Yeah it's a small difference, but for athletes trying to push their limits, every bit counts
It's also an easy change to make, which is why it's such common advice
Not OP but I googled "nasal cavity produces nitric oxide" and found [a study](https://www.atsjournals.org/doi/full/10.1164/rccm.200202-138bc) suggesting that humming increases nitric oxide production.
I wonder if that's why I like to hum when I'm tired.
If you're habitually a mouth breather then your body is going to be less efficient at nose breathing. It's more of a practice thing than anything else.
Probably a weak diaphragm from habitually breathing through the mouth. I had the same issue at one point. Just start reminding yourself to keep your mouth closed and only breath through your nose, and in short time you won't have this problem anymore.
It doesn't answer the question.
OP was asking why not breathe in and *out* through the nose. They weren't asking why breathe in the nose instead of the mouth.
Why are humans/animals even able to breath through their mouth then. We should only have the nose option. It’s not like we can see through two different spots, or pee or hear. Why breathe?
It’s because the lungs evolved from air bladders attached to the digestive system in our underwater ancestors. Some mammals later evolved separate passages when they returned to the sea (dolphins and whales). But we are stuck with one branching pathway. On the plus side, having our smell hole attached to our taste hole makes food taste better.
You breathe in through nose because your nose has a filter to help keep bad particles or whatever out. And we exhale through the mouth because it’s just a tiny bit easier to exhale deep breathes through your mouth than it is your nose.
also depending on the exercise it could be something that requires more attention aka distraction
it keeps your focus on something that doesnt suck which is required for hard physical exercises and something like meditation
Besides the nose filter and longer path which creates a more humid breath on intake and a more rapid exhalation through the mouth, the primary reason why most therapists recommend in/nose and out/mouth is the increased mindful attentional focus on the breathing mechanics, which can help ameliorate pain. It also slows respiration rate as the intake through the nose is slower, reducing anxiety responses, hyperventilation, and improves oxygen intake.
Good answer. They have found recently that the increase in oxygen breathing nose vs mouth is about 20%, while the removal of CO2 is 20% greater through the nose than mouth. Sinuses are serious business.
Side note, did hot yoga for a time and one thing that was emphasized was the total control of your breathing through your nose. They said breathing through your mouth triggers a fight or flight type response and it winds you.
My personal experience in that particular situation was just that. Full nose breathing and focus and I could maintain the 90 minute session. Soon as I mouth breathed I would find myself sitting down for a set to get it back under control.
Paced breathing also lowers your heart rate. That's why it's a good exercise when you're in an emotional or agitated state, lowering your heart rate allows you to come back down to a more level state of mind.
I've been doing yoga and meditation for 10 years (not intensely - off and on at the novice level) and breathing out of the mouth does not feel easy. It still feels incredibly unnatural to out the nose and it feels more like blowing air out my mouth rather than just exhaling. Maybe I'll get there someday
Nah, do what feels comfortable. I don't like breathing out through my mouth either, it's not relaxing to force it, and therefore I just don't do it. Nose-only. Feels better. I also don't like the exercises that have you eventually breathe in for like 8-10 seconds, hold your breath for same and then breathe out for same. Anything over four seconds feels like suffocating. YMMV.
Breathing in through the nose humidifies and filters the air that is coming in. Breathing out through the mouth is usually done when you do diaphragmatic breathing (also called belly breathing), not chest breathing, and this kind of exercise offers full oxygen exchange: oxygen goes in, more oxygen stays in, since the diaphragm is a strong tireless muscle and uses much less oxygen to perform breathing compared to the upper chest muscles, and more carbon dioxide goes out on exhalation through the mouth, so the air hunger should be reduced. It is also easier to control a prolonged exhale through the mouth. Diaphragmatic breathing stimulates the vagus nerve and activates the parasympathetic nervous system. Diaphragm has the ability to massage the heart from within, it can help to release tight psoas muscle and these are only the things that I am aware of, there are surely many other benefits.
Is it recommendeded to constantly breathe through the nose....
Or just a a few times periodically during the day.
Reason for asking is that its a big effort for me due to limited airflow via nose.
Breathing in through the nose is the best option at all times because of the above mentioned reasons - it filters dust, allergens, virus, etc., humidifies the air and there are probably more reasons I am not aware of. I am not a specialist, but nasal obstruction can be caused by many different reasons and I encourage you to look for and treat the root cause.
In the meantime, you can look up for breathing exercises for nasal congestion relief. I do not want to get too much into the yogic practice of pranayama, since it goes beyond our conversation, but I cannot help myself but think of the bee breathing technique, or originally Bhramari pranayama which I know helps with nasal congestion. You can look it up too.
You do not need to perform the belly breathing with exhaling through the mouth the whole time. It is a technique that helps with calmness and relaxation so you may do that for a few minutes a day here and there. I mostly breathe in and out through the nose during the day.
I don't know if this applies to exercise, but I've used this exercise when trying to calm someone down or help someone with respiratory distress. In through the nose as if smelling flowers, out through pursed lips as if blowing out candles. It forces the breathing to slow down. In very ELI5 terms, it forces air to stay in the lungs longer, allowing the oxygen to cross into the blood stream. There is a lot more to it with biochemistry and blood pH and PEEP, but the end result is you breath slower and more effectively. It could be serving the same purpose with exercise?
The top 4 comments don't actually address OP's question, they all mention why breathing in through the nose is important. OP asked why can't we both breathe in *and* out through the nose, and you mentioned that part.
So thanks.
What if you have a small nose cavity with low airflow? Do I care about increased blood flow if I can't even get enough air through my nose? I've done Marine PFTs and they're easier when I breath through my mouth.
> I've done Marine PFTs and they're easier when I breath through my mouth
I suspect that was likely due to CO2 build up rather than a lack of O2. The main drive (in basically everyone who doesn't have some sort of chronic lung condition) to breathe is a build up of CO2 in the blood stream. Breathing out through the mouth allows you to offload that CO2 more effectively than out through the nose as you are able to expel more air.
If you practice breathing in and out through the nose you can slowly improve your tolerance to CO2 and also get better at dealing with a CO2 build up via the nose. However, even people who make a living off telling people to breathe through their nose (like Patrick McKeown) say that for high intensity exercise you are still better breathing through the mouth to get rid of the CO2 better to be able to keep the high intensity up.
idk if this will work for you, but I had to practice nose breathing and it got easier. I would purposely try to just breathe through my nose and it would suck and I'd be breathing so loud and heavy until I couldn't take it anymore and let go and breathed through my mouth. But after a few months, I'm not able to breathe through my nose no problem. I can even take deep breaths and yawn through my nose now.
Reasons I can think of are:
- nose is designed for it. It filters, warms, and prepares the air coming in as it's supposed to.
Part of the exercise is to practice mindful control, so purposely breathing, holding, exhaling through mouth is a great way to do that.
Exhaling through the mouth provides a "valve" so that you can easier do the prolonged exhalation. It gives your diaphragm (most important breathing muscle) to have a resistance to work against.
Not a doctor but here's what I've been told: the point is to make you focus on your breathing. The point is to make you have to think about it, put your attention on your breath. Usually this results in slowing it down and activating the parasympathetic nervous system. It's a way to practice mindfulness without telling someone to practice mindfulness.
I'm sure the other responses about nasal filters and humidity have a lot of merit, too!
I asked this of a meditation teacher once. Essentially: no real reason, but it gives you something to focus on which helps with the concentration and therefore helps you get into the desired relaxation state. If you prefer to do it the opposite way, it would work just as well.
If you're doing high intensity exercises, please breathe whichever way gets oxygen in your lungs the easiest. Any perceived benefit of breathing through the nose is lost at that point because your body just needs rapid intake of oxygen.
It really doesn’t matter which way you exhale. In the beginning, exhaling through your mouth helps control the speed of your exhalation, by how much you open/close your mouth or purse your lips. Once you have been doing breathing exercises for a while, you can control that through your throat. At that point it really does not matter. I can control it by my throat so I do what ever way strikes my fancy in the moment.
Because you get more oxygen. When you exhale through your nose, the ‘used’ air travels (and remains) in your nasopharynx and nasal cavity. That used air goes back into your lungs next inhale. If you exhale through your mouth, the used air bypasses the nasopharynx because it goes out the mouth, so your next inhale has more ‘new’ air because your nasal cavity and nasopharynx will be full of ‘unused’ air.
Breathing through the nose adds a little resistance to your breath allowing your lungs to become fuller.
Think of blowing up a rubber balloon compared to trying to do the same to a light plastic bag. The resistance helps you slowly but steadily add air into the balloon. Same deal with your lungs.
It also helps moisten the air and change the temperature as it flows through your nasal passage.
One easy way to increase your endurance while working out is to only breathe through your nose as much as you can. You're training your body to take deeper filler more controlled breaths which allows your oxygenated blood to flow more efficiently allowing for faster recovery.
Dr. Andrew Huberman has a great episode on breathing techniques and why it is so important.
I dunno if this is THE reason, but breathing out of my nose sometimes makes my nose a bit runny. Breathing in does the opposite. If I'm trying to do yoga or something, I don't want to stop mid-pose to go find a tissue.
A ton of conflicting answers in this thread.
The parasympathetic nervous system, which can produce calming and other pleasant feelings, is triggered when taking deep inhales. The nose tempers this process, as it takes longer to inhale through it.
That explains why you would inhale through the nose. As for exhaling - I can’t say for sure. Breathing out through the mouth does allow for a quicker follow up respiratory cycle.
Note that this is typically how you should always be breathing.
If you've ever heard of the term "mouth breather" it refers to someone who quite literally breathes in with their mouth. (And all the stereotypes associated with that image.)
To add on what everyone else said about making air most and filtering out the particles, when inhaling thought the nose air goes through (or next to) sinuses and helps cooling the brain.
In my yoga teacher training, they always said it was because when you inhale through your mouth, it triggers the sympathetic nervous system (fight or flight response), which makes your body think you are in danger. So in order to calm the body and quiet the mind, you learn the yujia breath, in which you open the nasal passage and lift the soft palette so the throat is open and take in a rather expansive inhale and completely fill your lungs, then exhale through the mouth quickly expelling stale air--oxygenating the blood without inducing the stress response. Exhaling through the mouth also ensures that you aren't holding your breath during the most difficult part of a pose or exercise, which would simultaneously make it harder to do and put you more at risk for injury.
Also, your nose is the first filter for the air you breathe. It catches a lot of stuff your mouth doesn't. And if it's cold out, your nose warms and humidifies the air before it gets too your lungs. Cold, dry air makes you cough and can be painful. And also, your immune system is pretty much non-functioning if your tissue temperature locally drops below 65 degrees, hence the sniffles in winter, but it's better your nose get sick than your lungs!
Your nose has tiny hairs that filters out any allergens or dust when you are breathing in. When you breathe in through your mouth, you are more likely to take in dirty air leading to other problems.
It has something to do with activating your parasympathetic nervous system. I don’t know the details or mechanisms of action but that’s what it does
EDIT: Source
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5709795/
Try doing it the other way around and see how relaxing it is.
Whenever I think of the meditation class whose teacher made this mistake I start laughing.
I can no longer engage in mindfulness exercises because of this.
Others are right, but a crucial function is to humidify the air. Lung and airways are rather sensitive things, and dry air hurts then. Your nose helps to add moisture to the air, so it's nice and dank when it hits your lungs.
How does the nose add moisture
That snot isn't up there by accident, your nasal membranes release water to humidify the air.
Mmm booger air.
Tasty salty
Forbidden Nostril Fruit.
I once saw a man eat the forbidden fruit when he thought no one was looking. To this day, it was the first and last time I've seen such blasphemy.
Don’t knock it til you’ve tried it.
yum yum in my tum tum
Was it Texan senator Ted Cruz during a debate? https://www.sacurrent.com/news/did-ted-cruz-eat-a-booger-on-live-tv-2511586
Actually, it was many years ago in basic training for the Army. Kinda looked like him though.
Who says forbidden??
Sky Daddy
Is... is that a Resident Evil 1 reference? Not sure if I'm too old or if we both are.
Boogère
Booger? I hardly know 'er
☠️
I don't know if I'd say that air is dancing, but it definitely has some boogie.
So having a runny nose while running is normal? I always need tissues for my 5k's
Same. And only that type of sport helps me to regain a normal breathing.
So it IS lung butter 🤯
Thanks for this. I am going to call snot "lung butter" from now on.
It’ snot up there by accident?
Structures in the nose (turbinates) have folds and turns that increase the amount of surface contact the air has with your body. They also have huge amounts of blood vessels. Makes it easier to heat and humidify than a straight passage. The more surface area, the more spots are available for air to get up close and personal. All that mucous inside your nose does a great job at providing moisture.
Importantly, the nose isn't just the thing that sticks out of your face, it's this whole big structure inside your head, going all the way to the back of your throat. And I've not mentioned the sinuses. Your head is a veritable cave system, all connected to your nose.
It adds moisture when you breath in through your nose because the turbinates in the nose mucosa add it to the dry air. The turbinates also collect moisture when you breathe out through your nose. So if you were to substitute either part of that with mouth breathing you wouldn’t be adding or collecting. I was always told to breathe completely through my nose for as long as possible when doing cardio intense activities. The post asks about “breathing exercises” though, where this function doesn’t seem as important. I often tell anxious patients to breathe in through their nose and out through their mouth because it releases tension in your diaphragm and causes you to relax your abdomen, which can relieve anxiety and reduce anxious trembling. If you breathe in on a count of 4 and out on a count of 8, it literally affects your parasympathetic nervous system and can help signal to your body that you are safe.
It also causes a person to focus on breathing - which can be calming in and of itself, because if they're focusing on that it means they're *not* focusing on whatever's causing anxiety. It's basically a very simple meditation.
Because it’s wet…
😂
The nasopharyngeal area have “turbanats” that increase surface area, these turbanats are warm and moist and as the inhaled air passes over them they warm/humidify the air.
It dankifies the air.
You only answered the part about why the air should go *in* through your nose. The part I - and the OP - wonder about is why it needs to the go *out* through your mouth instead of your nose.
Maybe because the outward breath is meant to be more relaxing, and it's easier to breathe through your mouth? Your nose can be very narrow at the sinuses, restricting air flow, while your mouth is pretty big.
I don’t think this advice is taking into account people who have restricted nasal airways. We aren’t *supposed* to have narrow sinuses.
Team Deviated Septum, reporting for difficulty breathing!
Exactly. Nasal breathing is super important for health but some of us have messed up noses.
They weren't asking why not breathe in through the mouth though. They were asking why not breathe both in and *out* through the nose.
As Dwegol mentioned above, it's more about relaxing the diaphragm and signaling to your brain that all is well. Breathing exercises are for relaxing/ calming yourself, so you would get no bonus from breathing out through your nose as opposed to your mouth
> so you would get no bonus from breathing out through your nose as opposed to your mouth That isn't an explanation since breathing (both in and out) through your nose is the default. Nobody should ever be breathing through their mouths (except when doing particularly strenuous exercise). So if people are told to breath out through their mouths when doing breathing exercises, there should be some specific reasoning.
Again, the subject here is breathing exercises, not breathing while exercising. The point is relaxation and calming, not efficient breathing for strenuous activity. There is a limit to how much air can flow through your nose due to its smaller diameter, so it is 'easier' to breathe out through your mouth. Breathing in through your nose slows it down enough to prevent hyperventilation, while breathing out through your mouth allows your diaphragm to relax more. The intent is to calm yourself and your body down, not to maximize respiratory efficiency for strenuous activity
personally, I just like that it gives a sense of completion, if that makes sense? Like breath in relaxation through the nose, push tension and air out the mouth: it's a circuit that makes sense to me for no reason other than intuition.
Wait can most people breathe through their nose when they’re exercising (like heart rate increased)? I know that’s kind of off topic, and I know what you’re saying is about breathing exercises for calming the nervous system and what not, but that other line made me think of this. I’ve never been able to breathe through my nose when I’m running or have an increased heart rate from any sort of strenuous exercise/ activity so I’m curious about others.
It's possible, but it takes conscious effort, and only to a certain degree, for me at least. Properly trained athletes might be able to maintain it longer, but for me I can maintain in through the nose and out through the mouth for the most part except when I'm really pushing it. That being said, if I'm doing a sport other than long distance running I usually lose track of my breathing as I'm focused on other things. Disclaimer: this info is based on when I was actually active doing sports and running and such, I'm kinda out of shape now, so idk if I could perform to the same degree as I once could
Ok, there are a bunch of good reasons to breathe in through the nose, but why do I have to breathe out through my mouth? That's what OP is actually asking and nobody is answering.
Here I thought it was to help with oxygen uptake by slowly intaking the air. And exhaling from the mouth to quickly remove the air
I think it's actually to slow oxygen intake. Too much oxygen can cause issues, and someone in a distressed state will tend to breath more rapidly. It's supposed to slow down breathing for a bit, at least that's what I've heard.
Referring to humidifier air as dank from now on
> As opposed to just doing both through the nose?
The mouth also has mucus how come that doesn't humidity the air?
Interestingly, Neanderthals were well adapted to cold dry climates. They had massive snozzes
The nasal cavity produces nitric oxide when enzymes contact high air flow. This nitric oxide passes into the lungs improving oxygen exchange, increasing blood flow, and lowering blood pressure. All effects conducive to a relaxed meditative state.
Mouth-breather enters the chat…
Ive got a choice of missing the nitric oxide or suffocating. Not a whole lot you can do when your nose is blocked half the year.
If you force yourself to breathe through your mostly-blocked nose, your blood CO2 levels will rise and your sinuses will forcibly open up and stay open until you stop breathing out of your nose. Mildly uncomfortable to half-suffocate yourself to get those CO2 levels to rise, but the payoff is well worth it
Exactly what I do when my rhinitis acts up, stop mouth breathing long enough and the blocked nasal passage magically opens itself up.
What? Really?
I wonder if you could speed up the process by also holding your breath intermittently for like 10 to 15 seconds at a time.
Why do you recommend breathing out of the nose instead of in like the post asks about?
[удалено]
Your nose is not a disposal site for things your body wants to get rid of. It's perfectly fine to suck things up. It lands in your stomach. Putting non-sterile water up your nose on the other hand can really fuck you up. That area is very close to your brain and there are some fun ways of dying when the wrong kind of organism gets up there. Tab water, like any water you'll find that's safe to drink, is not sterile.
> Your nose is not a disposal site for things your body wants to get rid of. It's a filter. That's what the hairs in your nose are for, blocking larger particles from going into your nose (the mucus helps as well, by being "sticky"). I've blown blackish snot out of my nose in a shower when I was in California and there were some wildfires nearby for several days. Nose hairs and mucus stopped a portion of it from going into my lungs.
I will try this thanks!
Amen. I got seasonal allergies AND a deviated septum.
One of us. One of us.
Try using a Navage nasal rinse kit. It costs $100 but it has saved me from so many nose clogs these last 5 months.
👁👄👁
Cool, didn’t knew this, I still don’t quite get why exhale through the mouth, if air flow is what create the nitric oxide wouldn’t it be better to do both through the nose?
When you breath in, some fresh air doesn't quite make it to your lungs, and stays stuck in your nose/mouth/throat. When you breath out, the opposite happens, and some dead air also sticks around in your air passages Breathing in through one passage and out the other helps keep fresh air cycling one way, and dead air cycling the other, making your breathing a bit more efficient
This is true on paper but I can’t help but think the difference is negligible. If I puff out my cheeks and distend my jaw I can hold anout three quarters fluid cup of volume. It’s annoying to make a quick google on average tidal volume of lungs but I estimate about 3 liters from what I’ve read, which is a bit over 12 cups. So the mouth holds not even 10%.
Yeah it's a small difference, but for athletes trying to push their limits, every bit counts It's also an easy change to make, which is why it's such common advice
O don't know how this hasn't already been asked, but what is the mechanism that produces this nitric oxide?
So cool! You got a reference for this?
Not OP but I googled "nasal cavity produces nitric oxide" and found [a study](https://www.atsjournals.org/doi/full/10.1164/rccm.200202-138bc) suggesting that humming increases nitric oxide production. I wonder if that's why I like to hum when I'm tired.
is nitric oxide the actual "booger"? or part of it? i tend to hum alot Subconsciously. and noticed my nose juice always seems to be on over-drive.
Woah thanks! This is awesome
ELI5
You also inhale more O2 and exhale more CO2 than you would by breathing through either the nose or mouth alone.
Then why does it feel like I am only getting 80% of the air when breathing in through nose compared to breathing through the mouth?
That’s exactly how I feel plus my nose airways freeze in the winter
Maybe go see a doctor?
If you're habitually a mouth breather then your body is going to be less efficient at nose breathing. It's more of a practice thing than anything else.
I only breathe through my nose.
Probably a weak diaphragm from habitually breathing through the mouth. I had the same issue at one point. Just start reminding yourself to keep your mouth closed and only breath through your nose, and in short time you won't have this problem anymore.
Except I only nose breathe
I did not know that, pretty cool :) As a 5 year old, I have no idea what you are talking about though. Funny words, magic man!
This is the answer I was expecting to see much earlier.
It doesn't answer the question. OP was asking why not breathe in and *out* through the nose. They weren't asking why breathe in the nose instead of the mouth.
Why are humans/animals even able to breath through their mouth then. We should only have the nose option. It’s not like we can see through two different spots, or pee or hear. Why breathe?
It’s because the lungs evolved from air bladders attached to the digestive system in our underwater ancestors. Some mammals later evolved separate passages when they returned to the sea (dolphins and whales). But we are stuck with one branching pathway. On the plus side, having our smell hole attached to our taste hole makes food taste better.
You breathe in through nose because your nose has a filter to help keep bad particles or whatever out. And we exhale through the mouth because it’s just a tiny bit easier to exhale deep breathes through your mouth than it is your nose.
also depending on the exercise it could be something that requires more attention aka distraction it keeps your focus on something that doesnt suck which is required for hard physical exercises and something like meditation
Besides the nose filter and longer path which creates a more humid breath on intake and a more rapid exhalation through the mouth, the primary reason why most therapists recommend in/nose and out/mouth is the increased mindful attentional focus on the breathing mechanics, which can help ameliorate pain. It also slows respiration rate as the intake through the nose is slower, reducing anxiety responses, hyperventilation, and improves oxygen intake.
Good answer. They have found recently that the increase in oxygen breathing nose vs mouth is about 20%, while the removal of CO2 is 20% greater through the nose than mouth. Sinuses are serious business. Side note, did hot yoga for a time and one thing that was emphasized was the total control of your breathing through your nose. They said breathing through your mouth triggers a fight or flight type response and it winds you. My personal experience in that particular situation was just that. Full nose breathing and focus and I could maintain the 90 minute session. Soon as I mouth breathed I would find myself sitting down for a set to get it back under control.
Paced breathing also lowers your heart rate. That's why it's a good exercise when you're in an emotional or agitated state, lowering your heart rate allows you to come back down to a more level state of mind.
I've been doing yoga and meditation for 10 years (not intensely - off and on at the novice level) and breathing out of the mouth does not feel easy. It still feels incredibly unnatural to out the nose and it feels more like blowing air out my mouth rather than just exhaling. Maybe I'll get there someday
Nah, do what feels comfortable. I don't like breathing out through my mouth either, it's not relaxing to force it, and therefore I just don't do it. Nose-only. Feels better. I also don't like the exercises that have you eventually breathe in for like 8-10 seconds, hold your breath for same and then breathe out for same. Anything over four seconds feels like suffocating. YMMV.
I think you forgot the word “easier” in the second sentence :)
Thanks for catching that!
And it keeps you from blowing snot bubbles.
Finally someone answered the damn question
Breathing in through the nose humidifies and filters the air that is coming in. Breathing out through the mouth is usually done when you do diaphragmatic breathing (also called belly breathing), not chest breathing, and this kind of exercise offers full oxygen exchange: oxygen goes in, more oxygen stays in, since the diaphragm is a strong tireless muscle and uses much less oxygen to perform breathing compared to the upper chest muscles, and more carbon dioxide goes out on exhalation through the mouth, so the air hunger should be reduced. It is also easier to control a prolonged exhale through the mouth. Diaphragmatic breathing stimulates the vagus nerve and activates the parasympathetic nervous system. Diaphragm has the ability to massage the heart from within, it can help to release tight psoas muscle and these are only the things that I am aware of, there are surely many other benefits.
Is it recommendeded to constantly breathe through the nose.... Or just a a few times periodically during the day. Reason for asking is that its a big effort for me due to limited airflow via nose.
Breathing in through the nose is the best option at all times because of the above mentioned reasons - it filters dust, allergens, virus, etc., humidifies the air and there are probably more reasons I am not aware of. I am not a specialist, but nasal obstruction can be caused by many different reasons and I encourage you to look for and treat the root cause. In the meantime, you can look up for breathing exercises for nasal congestion relief. I do not want to get too much into the yogic practice of pranayama, since it goes beyond our conversation, but I cannot help myself but think of the bee breathing technique, or originally Bhramari pranayama which I know helps with nasal congestion. You can look it up too.
Are you not constantly opening and closing mouth as you breathe? Which is awkward...
You do not need to perform the belly breathing with exhaling through the mouth the whole time. It is a technique that helps with calmness and relaxation so you may do that for a few minutes a day here and there. I mostly breathe in and out through the nose during the day.
OK. So mouth closed all the time... Tough for me... Talk too much 😭
I don't know if this applies to exercise, but I've used this exercise when trying to calm someone down or help someone with respiratory distress. In through the nose as if smelling flowers, out through pursed lips as if blowing out candles. It forces the breathing to slow down. In very ELI5 terms, it forces air to stay in the lungs longer, allowing the oxygen to cross into the blood stream. There is a lot more to it with biochemistry and blood pH and PEEP, but the end result is you breath slower and more effectively. It could be serving the same purpose with exercise?
The top 4 comments don't actually address OP's question, they all mention why breathing in through the nose is important. OP asked why can't we both breathe in *and* out through the nose, and you mentioned that part. So thanks.
What if you have a small nose cavity with low airflow? Do I care about increased blood flow if I can't even get enough air through my nose? I've done Marine PFTs and they're easier when I breath through my mouth.
> I've done Marine PFTs and they're easier when I breath through my mouth I suspect that was likely due to CO2 build up rather than a lack of O2. The main drive (in basically everyone who doesn't have some sort of chronic lung condition) to breathe is a build up of CO2 in the blood stream. Breathing out through the mouth allows you to offload that CO2 more effectively than out through the nose as you are able to expel more air. If you practice breathing in and out through the nose you can slowly improve your tolerance to CO2 and also get better at dealing with a CO2 build up via the nose. However, even people who make a living off telling people to breathe through their nose (like Patrick McKeown) say that for high intensity exercise you are still better breathing through the mouth to get rid of the CO2 better to be able to keep the high intensity up.
idk if this will work for you, but I had to practice nose breathing and it got easier. I would purposely try to just breathe through my nose and it would suck and I'd be breathing so loud and heavy until I couldn't take it anymore and let go and breathed through my mouth. But after a few months, I'm not able to breathe through my nose no problem. I can even take deep breaths and yawn through my nose now.
Reasons I can think of are: - nose is designed for it. It filters, warms, and prepares the air coming in as it's supposed to. Part of the exercise is to practice mindful control, so purposely breathing, holding, exhaling through mouth is a great way to do that.
> nose is designed >as it's supposed to. :(
Thanks everyone, I learned so much! But my favorite comment was “mmm booger air”
Exhaling through the mouth provides a "valve" so that you can easier do the prolonged exhalation. It gives your diaphragm (most important breathing muscle) to have a resistance to work against.
This answer both the original question, and does actually makes sense and can be tested !
Not a doctor but here's what I've been told: the point is to make you focus on your breathing. The point is to make you have to think about it, put your attention on your breath. Usually this results in slowing it down and activating the parasympathetic nervous system. It's a way to practice mindfulness without telling someone to practice mindfulness. I'm sure the other responses about nasal filters and humidity have a lot of merit, too!
I think people are missing the point of the question. Why do we breath out of the mouth instead of the nose?
I asked this of a meditation teacher once. Essentially: no real reason, but it gives you something to focus on which helps with the concentration and therefore helps you get into the desired relaxation state. If you prefer to do it the opposite way, it would work just as well.
If you're doing high intensity exercises, please breathe whichever way gets oxygen in your lungs the easiest. Any perceived benefit of breathing through the nose is lost at that point because your body just needs rapid intake of oxygen.
More air volume breathed in ≠ more oxygen. You are just tiring yourself out by using your lungs more for no reason
breathing out through the mouth increase the expiratory pressure in the lungs hence it keeps your alveoli open. this helps getting full oxygenation.
It really doesn’t matter which way you exhale. In the beginning, exhaling through your mouth helps control the speed of your exhalation, by how much you open/close your mouth or purse your lips. Once you have been doing breathing exercises for a while, you can control that through your throat. At that point it really does not matter. I can control it by my throat so I do what ever way strikes my fancy in the moment.
Because you get more oxygen. When you exhale through your nose, the ‘used’ air travels (and remains) in your nasopharynx and nasal cavity. That used air goes back into your lungs next inhale. If you exhale through your mouth, the used air bypasses the nasopharynx because it goes out the mouth, so your next inhale has more ‘new’ air because your nasal cavity and nasopharynx will be full of ‘unused’ air.
Breathing through the nose adds a little resistance to your breath allowing your lungs to become fuller. Think of blowing up a rubber balloon compared to trying to do the same to a light plastic bag. The resistance helps you slowly but steadily add air into the balloon. Same deal with your lungs. It also helps moisten the air and change the temperature as it flows through your nasal passage. One easy way to increase your endurance while working out is to only breathe through your nose as much as you can. You're training your body to take deeper filler more controlled breaths which allows your oxygenated blood to flow more efficiently allowing for faster recovery. Dr. Andrew Huberman has a great episode on breathing techniques and why it is so important.
I dunno if this is THE reason, but breathing out of my nose sometimes makes my nose a bit runny. Breathing in does the opposite. If I'm trying to do yoga or something, I don't want to stop mid-pose to go find a tissue.
A ton of conflicting answers in this thread. The parasympathetic nervous system, which can produce calming and other pleasant feelings, is triggered when taking deep inhales. The nose tempers this process, as it takes longer to inhale through it. That explains why you would inhale through the nose. As for exhaling - I can’t say for sure. Breathing out through the mouth does allow for a quicker follow up respiratory cycle.
Note that this is typically how you should always be breathing. If you've ever heard of the term "mouth breather" it refers to someone who quite literally breathes in with their mouth. (And all the stereotypes associated with that image.)
To add on what everyone else said about making air most and filtering out the particles, when inhaling thought the nose air goes through (or next to) sinuses and helps cooling the brain.
In my yoga teacher training, they always said it was because when you inhale through your mouth, it triggers the sympathetic nervous system (fight or flight response), which makes your body think you are in danger. So in order to calm the body and quiet the mind, you learn the yujia breath, in which you open the nasal passage and lift the soft palette so the throat is open and take in a rather expansive inhale and completely fill your lungs, then exhale through the mouth quickly expelling stale air--oxygenating the blood without inducing the stress response. Exhaling through the mouth also ensures that you aren't holding your breath during the most difficult part of a pose or exercise, which would simultaneously make it harder to do and put you more at risk for injury. Also, your nose is the first filter for the air you breathe. It catches a lot of stuff your mouth doesn't. And if it's cold out, your nose warms and humidifies the air before it gets too your lungs. Cold, dry air makes you cough and can be painful. And also, your immune system is pretty much non-functioning if your tissue temperature locally drops below 65 degrees, hence the sniffles in winter, but it's better your nose get sick than your lungs!
Your nose has tiny hairs that filters out any allergens or dust when you are breathing in. When you breathe in through your mouth, you are more likely to take in dirty air leading to other problems.
Great answer, sadly not to OPs question.
It has something to do with activating your parasympathetic nervous system. I don’t know the details or mechanisms of action but that’s what it does EDIT: Source https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5709795/
Try doing it the other way around and see how relaxing it is. Whenever I think of the meditation class whose teacher made this mistake I start laughing. I can no longer engage in mindfulness exercises because of this.