One factor often overlooked in psychiatry is the quality of a person’s breathing especially those with a history of trauma, anxiety, panic symptoms or chronic stress. When stressed or anxious, there is a tendency to breathe more quickly and through the mouth. People often assume that breathing through the mouth is normal. It is not. We are designed and have evolved to breathe through the nose. In this next article, I will offer a few tweaks that may help the reader start to make corrections towards a healthier breath.
Much has been written about breathing over the centuries as far back as 1500 BCE, with the Ebers Papyrus from Egypt which offered a description of how nostrils were supposed to feed air to the heart and lungs, not the mouth. All animals breathe through their noses with one exception being dogs; they will breathe through their mouths on a hot day but are still mostly nose-breathers. As babies, we were born breathing through the nose but we know from studies 50% of children are mouth-breathers and probably the same goes for adults.
So what’s the big deal with mouth breathing? For starters, if you mouth-breathed as a child, you were more likely to have developmental issues with the downward forward growth of your face being not as well developed as well as airway issues. Your occlusion, the way you bite, and the way your teeth come together is affected. Your propensity to tooth decay, gum disease, cavities, dry mouth, and bad breath in the morning are all increased by breathing through your mouth. Mouth-breathers are more likely than nasal breathers to have sleep disorders and Attention Deficit Hyperactivity Disorder.
The nose has around 30 functions in the human body: it filters, moisturizes, directs the airflow, warms the air, registers the sense of smell, brings in oxygen, creates mucus, provides a route for drainage for the sinuses, affects the nervous system, and a number of other functions. The nose is the HVAC of our respiratory system. We breathe through our nose at a slower rate, and its moisture and temperature control make for a better and more efficient system. Moreover, the sinuses produce a gas, nitric acid, that is released in the nasal cavity that sterilizes incoming air as a first line of immune defense, opens up the airways, and enhances the amount of oxygen that is taken up in the blood. Nasal breathing has a profound effect on sleep quality, oxygenation, and relaxation. Additional benefits of nose breathing including better blood flow throughout the body and higher oxygenation levels on the brain. One study even shows a connection between nose breathing and improved memory function.
What is carbon dioxide tolerance (CO2 tolerance)?
At the base of your brain stem, there is a collection of cells called the “central chemoreceptor” that checks the level of carbon dioxide in the blood. If there’s too much carbon dioxide, the central chemoreceptor tries to get you to breathe harder. We now believe that some of the genes involved in carbon dioxide sensing seem to predispose for panic disorder. Panic disorder patients feel like they’re suffocating even when they’re not. It turns out that the primary stimulus to breathe is not to inhale oxygen but to expel rising carbon dioxide in the body; your body maintains more than 95% blood oxygen saturation almost always. You feel an urge to breathe when carbon dioxide levels rise. The more sensitive you are to carbon dioxide, the sooner you need to breathe. Mouth breathing increases your sensitivity to carbon dioxide. This makes you want to breathe more. It’s a vicious cycle.
Learning how sensitive you are to carbon dioxide is a great place to start to improve your breathing. This will act as a benchmark you can work to improve daily. Here’s how you may test it:
Take 3 deep breaths in and out of the nose (if you can)
On the third inhale, breathe in fully and start the timer.
Now exhale as long and as slowly as you can.
Whenever you swallow, pause, panic, or breathe, stop the timer.
The time you get is your carbon dioxide tolerance—write it down somewhere.
How did you do? The higher your carbon dioxide tolerance the better. 20-40 seconds is average and less than 20 seconds means you have some work to do. The good news is that with a little practice you should be able to increase your duration relatively fast.
The goal is to teach “chemoreceptor flexibility” or CO2 tolerance to people so they can learn to become more flexible to carbon dioxide levels; this could happen by developing the ability to tolerate a certain amount of carbon dioxide buildup before it tells you it’s time to expel some air from your body. As your CO2 tolerance develops, your body will be able to tolerate higher levels of carbon dioxide before it begins to switch into emergency mode, where it triggers hyperventilation and an intense need to exhale and steady the breath rate. There’s a very close correlation between CO2 tolerance and stress/anxiety. The better control you have over your breathing, the better chance you will be able to center yourself when things get stressful with less anxiety.
Tips for improving your breath
Almost everyone can breathe through their nose whether they believe it or not with only a very small percentage of people (<1%) that can’t use their nose at all. If you are concerned that you’re one of those people that can’t breathe through their nose or if there is any chance you have obstructive sleep apnea, please check with your doctor before trying the below exercises.
Nasal breathing during the day: The fastest and simplest way to improve your breathing and carbon dioxide tolerance is to breathe through your nose at rest. Just start out with practice breathing for about 5 seconds per inhale and 5 seconds per exhale for several minutes a day but breathing entirely through the nose. We naturally slow our respiratory rate down and breathe in more appropriate volumes through nasal breathing. When you feel ready to start nasal breathing during the day for a longer period such as 30-45 minutes, I would recommend getting some 3M micropore tape. You can tear off a small piece-the size of a Charlie Chaplin moustache and stick it over the center of your lips. This will gently keep your lips shut without feeling restrictive or claustrophobic. I would suggest taking it slow wearing the tape gradually working up to one hour while actively resting, focus on breathing only through your nose; keep in mind that talking would be difficult during this exercise.
Nasal breathing while asleep: Nose breathing is essential for deep, restorative sleep. Mouth breathing while sleeping often leads to disrupted sleep, sleep apnea, snoring, and a feeling of lethargy the next day; the problem is that the tongue may fall to the back of your mouth while sleeping rather than remaining behind your front teeth as it naturally sits when your lips are closed—something that is corrected with mouth-taping. As you become more comfortable breathing through your nose during the day, the next step is to try it during your sleep using the micropore tape. When I’ve mentioned this idea to patients who are predominantly mouth-breathers, some are quite curious and willing to try it while others consider it absurd, unnatural, and associate it with suffocation which will not happen as the tape will just come off on its own if nose-breathing is not feasible. If you wake up with the tape on in the morning, you have clear evidence that you can actually breath through your nose. If the tape comes off during the night and that happens over the next few nights, then you should go see an ENT doctor and find out how you can become a nose-breather.
A more advanced adaptation is nasal breathing during exercise: Start out with brisk walking or light cycling. I have tried this several times during a moderate level morning hike. It will feel uncomfortable in the beginning and you may also have a runny nose at first. As you get more experience with this way of exercising, you’ll notice you actually start to feel rejuvenated at the end of the session as opposed to beaten. Cardio workouts help to improve your aerobic fitness and have a similar effect on improving your body’s tolerance to carbon dioxide.
Going from being a mouth breather to a nose breather is a process. It is by no means a panacea but there are health benefits with slower breathing through your nose. If you are someone who knows the quality of your breathing could be better and could also be effecting your sleep or stress level, please consider working on this issue. You don’t have to be an elite athlete to retrain your body and you may get surprising benefits. I would propose doing a 30 day experiment with the above exercises with the idea that the mouth tape is like training wheels and eventually your body would get the message to breathe through your nose even when you are no longer using the tape.
If you would like to learn more about this topic, you may want to read:
McKeown, Patrick. The Breathing Cure: Develop New Habits for a Healthier, Happier, and Longer Life. Humanix Books, 2021.