About 85% of People Only Breathe Out of One Nostril at a Time

Today I found out around 85% of humans only breathe out of one nostril at a time.  Even more interesting is that the pattern of switching from breathing out of one nostril to the other happens in a cyclical fashion, with about four hours or so between each switch typically; although, this can vary from person to person and vary based on your body position or nasal congestion.

The first known instance of someone studying this “nasal cycle” was German nose specialist, Richard Kayser in 1895.  How your nose accomplishes this switch is via erectile tissue in your nose, which is very similar to the erectile tissue in a penis or clitoris.  Erectile tissue will swell up in one nostril, mostly blocking it, and at the same time erectile tissue in the other nostril will shrink, opening it up for breathing.

Even more interesting is that depending on which nostril you are predominately breathing out of at any given moment, it seems to greatly affect your body and brain.

For instance, a study in 1988 showed that breathing through your right nostril significantly increases blood glucose levels, while breathing through your left nostril has the opposite effect.  It is speculated from this that abnormal nasal cycles, such as breathing through your right nostril for many years without a switch, may be one contributing factor in certain cases of diabetes.

Another study in 1993 showed that when you are breathing through your right nostril, you will use significantly more oxygen than when breathing through your left.

Most interestingly of all, yet another study published in 1994, showed that when you are breathing through your left nostril, the right hemisphere of your brain will be more active or dominant and vice-verse when you are breathing through your right nostril.

Even though this switching happens naturally in a cyclical fashion, you can affect it in more ways than just plugging one nostril or the other to force breathing through the one you want.  If you lay down on one side or the other, after around 12-15 minutes, the erectile tissue in the nostril on that side will begin to swell up and the other side will decrease its swelling so that if you are lying on your left side, then your right nostril will open up and your left nostril will close up.

It is thought that this nasal cycle could be the reason that when you sleep on your side, you will often switch sides throughout the night at very regular intervals, even if you weren’t in the slightest bit uncomfortable.  It could just be that your body needs to switch which nostril it is breathing out of, so you feel the urge to roll over to your other side while you sleep.

If you liked this article, you might also enjoy our new popular podcast, The BrainFood Show (iTunes, Spotify, Google Play Music, Feed), as well as:

Bonus Facts:

  • Research has shown that the nasal cycle gets weaker as you get older.
  • The nasal cycle is thought to be regulated by the autonomic nervous system via the sympathetic nervous system.
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  • That’s so interesting! Definitely learned something today! Thanks!

  • I only breathe out of one nostril courtesy of a deviated septum because my nose was broken years ago

    • Hi,

      I have had a deviated septum as well. But it happened this way my brothers head hit my nose at the edge of the nose close to eye on the left. So the outer nose bone there is dented inwards. This happened when i was about 10 years old. I have had deviated septum from then and then got rhino plasty surgery done in 2012 that removed extra bone growth. I would like to know how this issue has affected you. I feel i breathe more through my right nostril and hardly use left nostril. This has happened for so many years ! I do Jala Neyti kriya as well but it does not help in breathing more from left nostril. I would like to know how this deviated septum has impacted you ?

      • you may try to balance your nostril breathing by doing sukha kriya,
        you start by inhaling, fill up to max, then close your right nostril with your right thumb, and exhale from your left, inhale again from same left nostril, and now when finishing inhaling then you close your left nostril with your little finger on right hand and release the thumb from right nostril and let the air go through out from your right nostril. Inhale again from same right nostril, and shift to exhale through left again. Inhale from same left and shift to right when exhaling… Continue this way 6 to 7 minutes each day. You will balance your air flow equally in left and right nostril, and after few weeks, your airflow will be normal same amount in left and same amount in right.

  • I’ll just add, you might notice when you have a cold and you sleep on your side, some mornings you can breathe through your nose reasonable well, and other mornings you are completely blocked. Its because if the nostril you are breathing out of happens to be the lower one, it gets blocked when the mucus flows to that side, whereas if it is the higher one, it is left clear.

  • discovered in 1895? Rubbish? It has been known by Vedic practisers from india for hundreds if not thousands of years

  • what about breathing from mouth.

  • Wow, guess I’m one of the 15% that doesn’t have a messed up nose.

    • if 85% people do the opposite and you’re the 15%, you’re the one that’s messed up, statistically speaking 😀

  • “if you are laying on your left side….” Laying WHAT on your left side? Your cat? Your shotgun? Oh, maybe you meant “LYING on your left side….” (Same error in other sentences, also.)

    • Daven Hiskey

      @DanZ: “Your cat?” “Your shotgun?”

      Those are not complete sentences. There are other grammatical problems with your comment, but I’ll stick with those two.

      See, I can do that too. 😉 Really though, thanks for catching the typo. I fixed it. I only saw it in one place though.

      • @DanZ: “Your cat?” “Your shotgun?”

        Those are not complete sentences.

        “Actually, those were complete “sentences.” Sentences do not always require a verb. Sentence contain a complete thought. An interjection like “Oh!” is a complete sentence.

  • For years I thought I was weird for breathing like this. Until I found out my dad was the same, I didn’t realise the percentage was that high though. I also turn over a lot in my sleep. I might try sleeping with a plug in a nostril so I sleep better. 🙂

    (I dont believe there are any spelling errors etc. in there but please feel free to point them out for me.)

  • Then there are people like me, who can’t breathe out of either. Which is why those very same tissues mentioned in this article are being removed from my head soon 🙂

  • I breathed out of one nostril for 45 years, then I had my deviated septum straightened. It was an amazing experience to be able to breathe out fo two nostrils!

    • How much was the procedure to have you breath through 2 nostriles at the same time? Do you still cyle between useing one and the other nostrile or do you use 2 at all times?

      How long did it take for you to recover. Was there any unintended consequences or side effects with your procedure?

  • You were good until you got to here:
    “Even more interesting is that depending on which nostril you are predominately breathing out of at any given moment, it seems to greatly affect your body and brain.”

    Implying that the nostril you are breathing out naturally at a particular time is the cause for the effects you go on to describe (even though the effects you reference have to do specifically with Forced Alternate Nostril Breathing [FANB] as opposed to breathing through a particular nostril as the result of the nasal cycle).

    Then you go on to state some awesome facts gathered from your interpretation of the results of unnamed studies (always fun).

    Blood Glucose(Backon J. Changes in blood glucose levels induced by differential forced nostril
    breathing,, a technique which affects brain hemisphericity and autonomic activity. Med
    Sci Res 1988; 16: 1197-1199.): I can’t find a free version of the study you speak of (for some reason you referenced it but then didn’t list it in your references), so I can’t comment on this particular claim past what I’ve already stated: Most of the studies I have seen deal with FANB, not the nasal cycle. Positing a cause-effect relationship between the nasal cycle being interrupted (breathing through one nostril for many years) and long-term blood glucose levels, with the insinuation that somehow the fact that you’re breathing out of one nostril is a component of the blood-glucose level is ridiculous.

    More oxygen (http://www.vivekanandayoga.com/research_papers/19940715_btpnamaa.pdf): While your assertion is a simplification of the results of the study, I think many people will take it at face value to mean “if I breathe through one nostril or the other, I use x% more/less oxygen”. The study itself measured baseline results for groups of individuals before starting them on various yoga practices. Two groups of 24, each group split into a control (N) group that alternated breathing between nostrils, and an experimental group that used one nostril 4 times a day for 27 respirations (S used right, C used Left [there’s a typo on the chart on page 3, C is supposed to state ‘Left Nostril Pranayama’]). After a month of yoga these measurements were taken again, they found that, while all groups had an increase in oxygen consumption, only the experimental groups were statistically significant. As I said, you summed up the results, but left out a lot of information necessary to help define the context of those results. If you breathe through one nostril right now, you won’t increase your oxygen consumption, but if you practice yoga where breathing through one nostril is a specific critera for a month, then your baseline oxygen consumption (not holding your nose) will increase.

    Hemisphere activity: Can’t find this study, so I’ll assume your retelling of results is factual, but the assertion that one side controls logic and the other creativity is false, based on split-brain studies conducted in the 1960s that have been superseceded by studies that don’t suffer from hasty generalizations (they assume that, because split brain patients associated objects based on function for left brain and aesthetics for right, somehow that means that we are logical with our left side and creative with our right). The fact is that both sides play a part in both aspects of our self that are generally misattributed to one side or the other (language ability, math, spatial perception), and differ in the way they process the information. This (http://www.rense.com/general2/rb.htm) link describes it best:

    “The people behind the scanner test, clinical neurologists Gereon Fink of the University of Düsseldorf in Germany and John Marshall from the Radcliffe Infirmary in Oxford, had been pursuing the idea that the difference between the two hemispheres lay in their style of working. The left brain, they reckoned, focused on detail. This would make it the natural home for all those mental skills that need us to act in a series of discrete steps or fix on a particular fragment of what we perceive–skills such as recognising a friend’s face in a crowd or “lining up” words to make a sentence.

    By contrast, the right brain concentrated on the broad, background picture. The researchers believed it had a panoramic focus that made it good at seeing general connections; this hemisphere was best able to represent the relative position of objects in space and to handle the emotional and metaphorical aspects of speech. So, in a neat and complementary division of labour, one side of the brain thought and saw in wide-angle while the other zoomed in on the detail. “

  • I happened to look this up while I was breathing through my right nostril. Meaning I was using the left, logical, side of my brain. Makes sense to me since I decided to research this right after I woke up this morning.

  • Awesome stuff, i had thought of the possibilities like this but never decided to look it up till now. Often i wonder if sleeping on one side or the other influences the corresponding side of your brain. it seems i dream only while i lay on my left side (is that normal?) and the left nostril is usually never closed or plugged can that cause my brain to think differently?

  • Carlos, sorry I though you could read spanish, I was asking who did your septum surgery and where, I am looking for a surgeon with good experience to have mine corrected

  • I started reading this because my right nostril sounded silly breathing in because I was lying in my left side with my left nostril open. When I got to the part about nostrils switching I realized it switched to the right side

  • Not too sure about this but wouldn’t using more oxygen lead to greater rate of respiration and therefore lower glucose levels? So how could breathing with the right side increase glucose levels AND increase usage of oxygen?

  • This article is false. The main premise of this article is wrong and hence the entire article is wrong. The 4th source “We Breathe Through One Nostril at a Time” is a wrongly titled article that is an older copy of the Wikipedia article “Nasal Cycle”. The statement in that is attributed to webmd.com’s article “An Overview of Sinusitis”, which has nothing about the false statement “breathing through only one nostril is normal and happens to almost everyone”.

    The correct statement which is used in the Wikipedia article is:
    – At any given time, one nostril is more open and has the greater amount of air flow. The cycle has a periodicity of 4 hours on average, however it is highly variable. It is present in 85% of humans.

    This is very different from what Daven has used in the title of this article: “About 85% of People Only Breathe Out of One Nostril at a Time”
    So there’s a difference between these two situations:

    (1) 85% of people have different air flow amounts on each side of the nostril.
    (2) About 85% of People Only Breathe Out of One Nostril at a Time

    Please, use your sources carefully (Wikipedia, De-Fact-o.com). Use the right sources, stay away from bad ones, improve your reading comprehension and don’t give out incorrect information which misleads the public.

    • Daven Hiskey

      @Alan: “improve your reading comprehension”. I think you could take some of your own advice. 😉 If you’ll read it again, you’ll see this line in the above article: “Erectile tissue will swell up in one nostril, mostly blocking it, and at the same time erectile tissue in the other nostril will shrink, opening it up for breathing.” So I did explicitly state that it wasn’t fully blocked. Beyond that, I think you’re being a little overly pedantic on the rest, but that’s just my opinion. Essentially, you are primarily breathing out of just one nostril when this happens, with very little air flow through the non-open nostril compared to the open one.

  • There is no evidence (scientific, research, studies or otherwise) that for 85% of the population, “Erectile tissue will swell up in one nostril, mostly blocking it and at the same time erectile tissue in the other nostril will shrink, opening it up for breathing.”, and therefore your claim that “Essentially, you are primarily breathing out of just one nostril when this happens, with very little air flow through the non-open nostril compared to the open one.” – is entirely false, and has no scientific basis. If that is true, I could say that 94% of people having their first names with the letter ‘D’ don’t know what they’re talking about, and refuse to accept facts. But that statement is false so I would never make it. If I made it, and someone pointed it out, I would accept that I’d been wrong. Or I can continue to dig my heels in no matter what.

    I’ve pointed out that you got that statement from the Wikipedia article which falsely attributed that to a webmd.com article, which doesn’t mention *anything* like that, at all – not even close to it. <— Is that not significant for you to notice? I can accept you making a mistake and using an "unreliable" source but how can you continue to defend an article where the source has been wrongly attributed?

    I've struggled with years of nasal problems so I've read, learned and experienced a lot of things. I'm not being "pedantic", you're being inaccurate. There is a huge difference between the statements (1) and (2). #1 is simply commonsense, knowing that there's erectile tissue that swells up and down, so ofcourse there's going to be unequal airflow. #2 says: "One side is usually mostly blocked" – this is FALSE, and very different from #1. Having one nostril fully or even mostly blocked at any time is a medical condition (hypertrophy) which results in poor sleep, daytime exhaustion, and you're suggesting that 85% of people have that problem.

    Anywhere you look, you'll find research supporting #1 but not #2.

    So as I requested in email, could you please cite sources for your claim that "85% of people have one nostril mostly blocked"? There are no sources for that because that is a false statement.
    What the "reliable" sources said is this: Most people have unequal air flow in their nostrils. In other words, for only 15% of the public, the airflow is mostly equal.

    Don't oppose me emotionally because you have your ego behind this article and now have to defend it. Be open to facts and accepting the possibility that you were wrong.

    Go ahead, tell me how your article is still correct even though I've pointed out that the source (an old Wikipedia article) wrongly attributed it to the webmd.com article that doesnt say anything like that.

    Wikipedia has to be used very carefully. You have to look at whats being said and the sources used. And you can ask your brother to look at this and I assure you he cannot respond to the point I raised. He didn't read the article carefully.

  • Daven, here’s another way of explaining the point I’m trying to make: You’re saying that “One eye for 85% of people is mostly useless at any given time”, while science says “For 85% of the public, one eye is stronger than the other” (this is just an example, its not true). Both of these statements are VERY different, as you can imagine. One cannot be confused with the other and I cannot be called “pedantic” for pointing out the difference.

    You can do two things to prove your love for facts, logic and knowledge: (1) Prove me wrong using science (2) Accept that you were wrong. I welcome being proven wrong using science and facts, so go ahead and try.

  • Alan, baby, why are you so up in arms for such a small thing? For all intents and purposes, you only breathe out of a single nostril at any given time, making the nostril that is currently swelled with tissue mostly useless. You can still breathe out of it, but not very well at all.

    Have you ever heard of the expression “Making a mountain out of a mole hill”? You happen to be quite good at it, which is why he called you pedantic.

    You ARE being pedantic, if I hadn’t made it overly obvious by now.

  • First, let me thank Daven for taking the time to write this article.

    Second, let me thank Alan. For any article written, it is always a good idea to have readers verify its veracity with sources etc.

    Some readers prefer a short summary. Others prefer details. For those who prefer the former, Alan is just pointing out that the title could be more accurate, as I misunderstood too at the beginning.

  • This is me every night! When I lie on my left side I can only breathe out of my right nostril and when I flip, then the right nostril plugs up and the left opens. IT DRIVES ME INSANE

  • While I’m enjoying reading the articles on this site, the fact that the author frequently responds to criticism in such a passive aggressive manner is putting me off. Put simply, typos are annoying. Incorrect use of contractions and possessives is annoying. Grammar nazis in the comments section are equally annoying. However, when the author begins to lengthily defend themselves in the comments, it comes across as unprofessional and dissociates them from the audience. I’m not expecting a reply, it’s just an opinion.

  • Im curious if this has any relation to Ptosis, or Sinusitis. The reason I ask is because I have noticed that one eye is stronger than the other and it is the left eye, I got the impression that using a Neti Pot is the best way to clear your nasal passages ?

  • So is this pretty much a deviated Septum or what?? because i am having a horrible time breathing through my nose at the time!

  • @Steve… Thousands of years? Really? So you’re saying there were ayurvedic cave men? Interesting.

    @Olive… If grammar bothered me as much as it bothers you i’d probably stay away from forums or Youtube.

    @OP… Thanks for the article. I’ve always wondered what this issue was. It’s good to know others have experienced it and it’s not just from all the cocaine i’ve used.

  • @Steve M, 2000 or 3000 years are “thousands of years”, Brahmanism or Buddhism are that old and they were not cave men.

  • Alan isn’t being pedantic. He wants to trace the data that contributed to the conclusions drawn by the author of this article to see whether he draws the same conclusions. That’s how scienctific inquiry works. The purpose is not to “prove someone wrong”, but to test validity of assertions, especially when those assertions make one think, “Huh? That doesn’t sound right!” (such as one having better logical reasoning skills when breathing through the left nostril. Or something.)

    If Alan makes a habit of considering the source when faced with medical or scientific reports, I can guarantee that there have been times when he has found that some bizarre claims do have evidence to support them.

  • http://www.todayifoundout.com/index.php/2010/03/about-85-of-people-only-breathe-out-of-one-nostril-at-a-time/ that has been known for THOUSANDS OF YEARS. Since teh rishis developed ayurveda. These yogis observed how we live.

    I think you need to change that. It’s funny because you include a pic of shiva – lord of yoga and siddha and most likely ayurveda too, but don’t mention it was observed until some German dude came along… rididculous.



  • I learned from this article that there is erectile tissue blocking nasal flow, makes sense since the congestion felt say dry and didn’t produce a lot from blowing my nose. To alleviate I use a q-tip dipped in either sesame oil (non-cooking type) or olive oil. It helps with the dryness but I also read an article where the commenter said they had great success with colloidal silver. Not sure how they applied it but they said they were going to try in Neti pot. Just wondering if anyone has tried this?

  • Well i always lay on my right side and my right nose is always cloged so i think that you just might be on to something. Plus i do tend to be really creative sometimes

  • Hey Daven, just to add to your post. Actually in usually all cases the state of the body determines how the nostrils open up or close. What you said is entirely true but you said that when breathing out of the left nostril ones blood glucose levels decrease. It’s really the opposite, when the body’s blood glucose levels are low the left nostril opens up. When you said that left nostril breathing increases creativeness and imagination due to the activation of the right hemisphere of the brain, it’s actually the opposite, that is when the right brain is active the left nostril opens up and this happens when one is relaxed and at rest because that decreases adrenaline levels make one relax and increases right brain activity with the simultaneous opening of the left nostril. In the same light you will notice that when you are anxious/nervous or in a state of logical activity your right nostril opens up, it’s the same concept. But I agree with you. This knowledge of the behaviour of nostrils in relation to the body’s state was already known by vedic practitioners of India thousands of years ago, and they actually used this knowledge to intentionally alter the state of their body by controlling which nostril they were breathing from. this is what lead to the rise of the “Anulom Vilom” technique of Pranayam (science of controlled breathing) within Yoga.

  • it’s true that this is normal for 85% of people but it is a highly inefficient design. I know this because I have literally lived the benefits of life without the nasal cycle. Three years ago, at the age of 22, I started using afrin after a cold – eventually I was using it everyday to breath 100% through both nostrils.

    The increased oxygen intake was life-changing. Personality wise I became more social, more creative, much more attentive and motivated at work, and in many ways more emotionally aware and ethically conscious. More than that, though, I dropped nearly 40 lbs in a few months and went from what was a lifetime of obesity and poor health to being a marathoner and a globally ranked ironman triathlete (I also went vegan around the same time so that was also a contributing factor).

    This is not by any means an endorsement for afrin/oxymetazoline HCL. Because, 3 years later, in January of this year, my turbinates hypertrophied to the point where afrin was only opening each up about 40%. After taking months to kick my afrin dependency my nose was still completely clogged. One week ago I went through turbinate reduction surgery to remove what the doctor told me was permanent turbinate hyperplasia from afrin abuse. I’m still healing, but my nostrils are once again cycling open/close like before.

    One is always open 100%, and the other about 40%, and they switch periodically. It’s my hope that once I’m fully healed, my nostrils will be open 100%/80% or something similar. I’m hoping for better results than before my afrin use because in addition to removing hypertrophied tissue I also had my septum straightened slightly and an air pocket removed from my middle turbinate – so there’s much more room to breath, pun unintended.

    Overall, I’m definitely glad I started using afrin because it set my life on a totally different course during very important and formative years – I’m just grateful to live in a time where conservative surgical options were available to correct the damage.

    The experience taught me one thing: Nature and evolution aren’t perfect. Appendicitis, foot pronation, and poor vision are just some of the evolutionary traits that plague the vast majority of people. I think this “nasal cycle” is just another counterproductive evolutionary characteristic that humanity did not breed out prior to the advent of industrialization. Like other inherited deficits, it will likely stay with us until it is removed though genetic design or broad-stroke surgical intervention much like we do with circumcision or appendectomies.

    • First of all I think what you are referring too is inflammation which is what Afrin treats. Therefor you probably had or have allergies. Afrin helped you breath better and helped your life. Although your only supposed to use it a few days. This all has nothing to do with the sleep cycle. it could also be you have a small nose and deviated septum which caused breathing problems. .

      Secondly their is no proof that 85% of people experience poor nasal breathing one side every few hours. Yes their is a nasal cycle however this does not mostly block breathing from one nostril. This cycle has a purpose though and is not an evolutionary mistake. Here is one explanation of what it does from a medical source. However their are many different reasons it helps us.

      …it makes our sense of smell more complete. Different scent molecules degrade at different rates, and our scent receptors pick up on them accordingly. Some smells are easier to detect and process in a fast-moving airstream like the decongested nostril, while others are better detected in the slower airstream of the congested nostril. Nasal cycling also seems to keep the nose maintained for its function as an air filter and humidifier. The alternating congestion gives the mucous and cilia (the tiny hairs up in your nose) in each nostril a well-deserved break from the onslaught of air and prevents the insides of your nostrils from drying out, cracking and

      Also evolution is not proven and could easily be a lie however adaption is real. Regardless our bodies are fine and so is most people’s breathing. Some people have large deviated septum and small nasal openings because of birth problems, genetics from their parents or injuries. However that is a small percentage. God created us and our body parts have purposes. We’re not perfect but their is nothing in A human Without meaning.

      Also poor vision has nothing to do with evolution. people always used to have good vision. The poor vision comes from the last few hundred years. Where lots of pressure has been put on our eyes. From reading and in the last century from electronics. Also appendicitis is a lie its proven that we need the appendex. Scientists and doctors worship of evolution caused so many misdiagnoses and problems in society. Evolution is most likely not real even if it were it has no place in the medical field.

  • It would be very helpful if, when reference is made to research articles, the author could give details of these articles.

  • Is there any problems if we breathe out of one nostril ?…..
    Is there any remedy or operation to take place when man is getting older?…..

  • Good information, except….This was not known first in 1895, this was known since thousands of year to Indian Sages, even they knew lot more than that, they used to do meditation on mountains/under the tree without food for many days, they knew how to keep consumption of oxygen by body lower. Also they used to keep their one arm on Y shape wooden kind of stand about 1.5 feet height, arm placement in a specific position presses one or more veins by which both nostrils can breath and intake more oxygen. See images of Indian Sages on Google.

  • “Most interestingly of all, yet another study published in 1994, showed that when you are breathing through your left nostril, the right hemisphere of your brain will be more active or dominant and vice-verse when you are breathing through your right nostril. “http://psychology.about.com/od/cognitivepsychology/a/left-brain-right-brain.htm this study about right vs left brain thing has been falsified along time ago and is an urban myth okay.. ITS FAKE

  • My left nostril is clear but I can barely get air in it when I block my right nostril. I believe this blockage has caused me headaches and hypertension?

  • There was something about our perception of smell being affected, it was at VSauce youtube channel I think.
    Since one of the nostrils is more open, the air flows more quickly allowing us to detect particles that are quickly recognised.
    However, the other nostril (the one more closed), limits the air passage, hence the molecules do not move through so fast, so the receptors have time to recognise the molecules that are more complex, which gives us constant…-ish, wider sense of smell, than just breathing strictly through just one nostril.

  • I guess they mean 85% of WHITE people.

  • Good Article. If you spent an hr trying to prove the author wrong u need a life.

  • World needs more Alans, and definitely more scientific literacy. Authors should appreciate being corrected, and should be more careful regarding their assertions. Sadder still, people will believe anything they read.

  • i think this is true..in my part, i can only smell the scent of food on the left side

  • Aw yeeeeee im in that 15%

  • I meditate 2 hrs a day and regular meditation helps to balance breathing through both the nostril ultimately to lead to breathe through center path in a Yogic way. Mystic Thirumoolar has given a lot of information in this. Center breathing also raises Gundalini up.