How Mouth Breathing Can Undermine Your Health—and Easy Ways to Fix It

Take a big breath in—pause for a moment—and now slowly let it out. While most of your breathing is automatic, learning how to consciously work with these two diametric movements (like you just did) can unlock major benefits for your physical, mental, and emotional health. From calming anxiety to relieving sleep apnea, we talked to breathwork experts about the subtle alchemy of “belly breathing,” why we’ve forgotten the power of this simple practice, and how you can easily incorporate breathwork into your busy life.

Before getting started, it’s important to understand the basics of your respiratory system. At the base of your ribcage is a dome-shaped muscle called the diaphragm—this is the most essential part of the body to befriend if you’re committed to improving your breathing habits. As you inhale, the diaphragm contracts and allows the lungs to expand as you take in air. When you exhale, it rebounds to its natural shape as the lungs contract and push air out of the body. Intentionally breathing into the diaphragm strengthens this essential muscle and over time allows you to consistently take fuller, more nourishing breaths. 

But the diaphragm isn’t the only important muscle involved in breathing. Between each rib bone are intercostal muscles that help expand and shrink the chest cavity with every cycle of breath. As you learn more effective breathing techniques, you strengthen these muscles. Instead of feeling like your breath is a simple up-and-down motion of your lungs, you’ll be able to feel the full 360-degree expansion of your rib cage. 

As you bring air into your lungs through your nose or mouth (although you’ll learn below why nasal breathing is better than mouth breathing), oxygen is diffused into the bloodstream and carried to your cells. This supply of oxygen, combined with the sugars from the food you eat, allow your cells to produce energy and function at optimal levels. Carbon dioxide, a byproduct of the energy conversion in your cells, is then transported back into your lungs and expelled when you exhale. These two processes—inhaling oxygen and exhaling carbon dioxide—are automatic functions of the respiratory system, but learning how to breathe more consciously can significantly improve the functioning of your body and mind.

It’s easy to think you’re breathing correctly when the majority of it happens unconsciously. But it turns out a healthy breath actually requires a decent amount of thought.

James Nestor, journalist and best-selling author of Breath: The New Science of a Lost Art, traveled the world to discover exactly where we lost the ability to breathe properly—and how to relearn this crucial skill. 

“A lot of us assume we're breathing just fine because we're alive,” says Nestor. “But just being alive is a lot different from being healthy. Working with researchers at Stanford I learned that the majority of the population suffers from some sort of chronic respiratory illness—be that chronic sinusitis, snoring, sleep apnea, asthma, or COPD. And these are growing every year to where it’s reaching epidemic levels across the world.” 

Air pollution, exposure to cigarette smoke, and airborne diseases are major factors in the increased rates of respiratory illness, but there’s also a lesser known culprit behind these skyrocketing ailments: mouth breathing. While it’s certainly fine to breathe through your mouth when you have a stuffy nose or during a specific breathwork practice, it’s not effective—and can even be damaging—when it’s your default setting. 

“Our nose serves enumerable functions,” Nestor explains. Nasal breathing releases nitric oxide, which widens blood vessels and allows more oxygen to reach the body’s tissues. Nestor notes that nasal breathing also filters and moistens air as it enters the body, along with promoting relaxation by engaging the parasympathetic nervous system. “We don't get any of those advantages when we breathe through our mouth.”

Breathing through your mouth not only circumvents the beneficial functions that are naturally built into your nose but it also dehydrates your body quicker and leads to higher rates of periodontal disease and cavities. 

Apart from mouth breathing, most people shortchange the health benefits of the breath by not fully using the diaphragm to inflate the belly and create more room for the lungs to expand. Valentina Jaramillo, a San Diego-based breathwork practitioner and co-founder of Rise In Love, facilitates workshops based on the ancient Tantric principles of working with the breath to improve mental, emotional, and physical health. 

“We tend to breathe by just expanding our thoracic rib cage and not by expanding the belly,” Jaramillo explains. “I think in the Western world we don't like the belly. We tend to suck it in, especially for women. But constantly contracting your belly doesn't allow your lungs to inflate or expand as much as they should. And if we aren’t getting enough oxygen it’s harder for our muscles to create energy, for our heart to pump blood to our limbs, and for our digestive system to work correctly. A breathwork practice allows our bodies to have the oxygen we actually need for all our biochemical processes to function well.”

Sucking in your stomach doesn’t only impact the quality of your breath—it can lead to serious physical ailments such as organ prolapse, pelvic floor issues, asthma attacks, and chronic headaches because the abdominal muscles aren’t ever allowed to relax. This pattern of shallow breathing can also impact your mental and emotional health by keeping your nervous system in a constantly elevated state of fight-or-flight.

“When we’re stressed our breathing gets very short, we breathe too much, and we trigger stress hormones like cortisol that prepare us for danger,” Nestor says, “which, evolutionarily speaking, is a good thing—but in the 21st century we’re constantly having this reaction throughout the day when things aren't actually dangerous. For example, you open up your email and you're stressed out about what your boss wrote to you. This constant state of stress sends our body the wrong signals.”

So how did we get to this point where our breath is constricted, shallow, and pushed primarily through the mouth? Alan Dolan, a breathwork practitioner with more than 17 years of experience leading breath-coach trainings at his retreat center in Lanzarote, Spain, has an idea.

“I think one of the reasons we forgot [how to breathe properly] is due to the Industrial Age where we moved from an agrarian connection to nature into the Industrial Revolution where science and technology became king,” he explains. “We lost our connection to the natural world and forgot that nature is an incredible teacher.”

Nestor’s research backs up this claim by shining a light on how breathwork was—and still is—a critical part of many cultures that emphasize a more holistic approach to health.

“If you look at qi gong, ancient Hindu cultures, and Chinese scriptures they’ve emphasized the importance of the breath for thousands of years,” Nestor says. “Many of the incredible claims these cultures make about the breath are now verified through science. Yes, you can heat your body up through breath, you can straighten a scoliotic spine, you can vastly reduce anxiety, you can relieve snoring and sleep apnea—all through the way in which you breathe. So it's not news to anyone, but I suspect most people think that something so subtle and obvious couldn’t have such a huge impact.”

The good news is that both Dolan and Nestor are noticing an increased desire in the West to learn how to breathe for better health and apply these ancient practices to modern life. “We've just had a global pandemic that’s robbed us of the ability to breathe,” says Nestor. “People are now thinking that it might be important in their day-to-day life.”

We asked Nestor, Dolan, and Jaramillo if there was an ideal way to breathe, and all three answered with the same technique—diaphragmatic breathing.

“I just call it healthy breathing or ‘human’ breathing,” Nestor says. “Because it’s how we've been designed to breathe. All you have to do is look at nature as your guide. Look at a healthy infant breathing. Look at your dog breathing when it's sleeping. You can see they have healthy diaphragmatic motion.”

Diaphragmatic breath (also called belly breathing) involves deeply inhaling into the stomach area like you’re inflating a balloon and allowing the breath to travel into the upper chest. If you rest your hand on your belly you can feel each breath push gently into your palm. The exhale simply deflates that interior “balloon” so you can feel your rib cage and stomach lightly contract back to their resting state. But remember, it’s not just about moving your diaphragm: It’s also crucial to take your inhales and exhales through the nose to reap the benefits of your olfactory filters. 

“Diaphragmatic breathing gives the nervous system the rest-and-digest message as opposed to the fight-or-flight response that happens when we breathe into the upper chest,” explains Dolan. “So if we're breathing solely in the upper chest, we’re constantly telling our nervous system that we’re in danger.” 

Consistency is also key when you start to work with this breathing technique. Similar to the way that eating vegetables won’t improve your health much if you continue to consume large amounts of highly processed junk food, practicing diaphragmatic breathing only once a week won’t make a big difference. Jaramillo recommends doing short bursts throughout the day, perhaps 10 minutes after waking up and 10 minutes before bed, to get your body used to this new pattern. Eventually you can practice it during your morning commute, while you sit at your desk at work, and even when you exercise. Over time, diaphragmatic breathing will become your default setting—just as nature intended. 

From increased mental clarity to stronger muscles, the benefits of taking slower, deeper breaths can have profound impacts on your health. Take a look at some of the top changes you can expect as you invite a consistent breathwork practice into your daily routine.

As our experts have explained, diaphragmatic nasal breathing helps thoroughly oxygenate the body so that your cells, organs, and muscles can work at optimal levels. At the same time it helps keep negative cellular responses—like chronic inflammation—at bay. 

“When you're breathing shallowly and in a state of heightened stress you get an inflammatory response throughout the body,” Nestor explains. “Your adrenaline kicks in, your blood sugar goes up, and your body inflames to cut off blood flow to less-critical areas when you’re in crisis mode. Having that constant state of stress throughout the day will wear your body down.” 

Nestor says that learning to effectively work with your breath can reduce chronic inflammation, which is linked to sleep apnea, arthritis, Type 2 diabetes, and other autoimmune disorders. A 2016 study published in BMC Complementary Medicine and Therapies tested subjects for inflammatory biomarkers in their saliva before and after performing yogic breathing exercises. Compared with the control group, the yogic-breathing group saw significant reductions in inflammatory biomarkers, suggesting that conscious breathing techniques could play a significant role in reducing the negative physiological effects of inflammation and stress.   

“Beyond just getting air into the body and expelling carbon dioxide, the diaphragm is actually a pump for our blood and our lymph system,” Nestor adds. “We need that constant movement in order for our bodies to operate normally. Constantly breathing through your mouth will impact these internal systems because you aren’t getting that fluidity of diaphragmatic motion.” The lymphatic system is part of your immune system that helps protect against bacteria, viruses, and parasites. As your body becomes more familiar with diaphragmatic breathing and turns it into muscle memory, you may experience less frequent colds or less severe cold symptoms. 

Chronic respiratory ailments, such as asthma and sleep apnea, may also be relieved through diaphragmatic and nasal breathing. A 2003 study from the European Respiratory Journal measured the impact of nasal and oral breathing on the restriction of upper airway passages that lead to obstructive sleep apnea. Researchers found that airway resistance and disruptive sleep patterns were significantly lower for participants who breathed through their nose during sleep than those who breathed through their mouth. A 2014 review published in Breathe examined multiple studies and concluded that breathwork training improved the symptoms, overall health, and psychological well-being of people with asthma. 

Apart from alleviating chronic ailments, learning how to breathe more effectively also has benefits for athletic performance. A 2019 article published in EC Pulmonology and Respiratory Medicine reviewed multiple studies on the physiological impact of nasal breathing and concluded that athletes can see significant changes in their performance, recovery time, and pre-game sleep quality if they breathe through their nose instead of their mouth. Nasal breathing produces higher levels of nitric oxide (which is essential in bringing oxygen to your cells) and allows for increased aerobic capacity, fewer instances of exercise-induced asthma, and improved homeostasis of heart rate and blood pressure. 

Apart from giving your body a major boost, learning how to breathe better can take a lot of pressure off your mind.

“Our culture is very intellectual,” Dolan says. “Which means we put a lot of emphasis on our minds. So our brains tend to be overstimulated, which isn’t great because if there's too much energy up top, there's a lack of energy down in the body. When you breathe diaphragmatically, it balances that out. You drop more into the body, feel more grounded, and are more connected to the physical aspect of who you are.” 

A 2017 study published in Frontiers in Psychology found that diaphragmatic breathing significantly increased the amount of time participants could stay focused on tasks that required sustained attention. Compared with a control group that received no breathwork training,  participants who were provided with instructions on diaphragmatic breathing consistently exhibited lower levels of cortisol (the stress hormone) and reported fewer negative thoughts. 

The connection between mental health and breath was further explored in a 2020 study published in Frontiers in Psychiatry where college students were taught SKY breathing—an advanced yogic breathwork technique—to mitigate stress and depression. Students were divided into either a control group, the SKY group, or two other mindfulness-based training groups that did not include breathwork. The researchers found that students who received the 30 hours of SKY training over eight weeks experienced a significant decrease in stress and depression and an increase in positive emotions and social connectedness.

A main part of Dolan’s job as a breathwork practitioner and trainer is to help his clients learn to breathe through their emotions. He compares this process to surfing: There will always be waves in the ocean (i.e., strong emotions to process) but if you know how to surf (i.e., use your breath) then you won’t fall into the water. As you become more adept at breathing through big emotional surges, you’ll likely start to notice that your body doesn’t internalize stress as much, allowing you to navigate difficult situations more safely and calmly. 

First things first: Don’t expect to go from zero to 100 in a single day. All the experts we spoke with emphasized that it’s important to start small when beginning to consciously work with your breath. Taking baby steps will help avoid burnout and will encourage your body to absorb this new technique as muscle memory and help build a stable habit. Start with picking one of these techniques and doing it for several minutes a day, then gradually increasing the duration or the number of times during the day that you engage with it. Try to be conscious of any changes you experience in your physical body, emotions, and mental energy: Being aware of these subtle shifts will help reinforce the healing benefits of this work. 

If you’re brand-new to breathwork, this is the technique to start with. More advanced practices build on the foundational knowledge you’ll gain once you master basic belly breathing.

This technique is great for strengthening the diaphragm and calming a busy mind. It does involve suspending your breath after each inhale and exhale, so be aware of whether holding your breath is emotionally triggering or physically taxing.

A common breathwork practice (or pranayama in Sanskrit) used in yoga, alternate nostril breathing brings balance to the right and left sides of the body. It’s also known to provide mental clarity, purify negative emotions, and bring a sense of calm when practiced regularly. (Note: This practice is not recommended if you have a stuffy nose because you won’t be able to take in full, deep breaths.)

Feeling a little hotheaded? This yogic breathing technique is great for cooling down the mind and body when you feel agitated. While it might feel a little silly at first, you’ll quickly be able to see how it can help regulate an activated nervous system.

Whether you’re brand-new to breathwork or have been working consciously with the breath for decades, there’s always something new you can learn from taking a few moments to be present with your inhales and exhales.

“Breathing is not complicated,” Nestor reminds us. “Look to nature as your guide. We've known how to do this for millions of years. We've just forgotten how to do it. Your body can remember—it just needs a little coaxing.”