The likely answer is that you are probably both of these at various times of the day and night, depending on what you are doing e.g. resting or doing physical activity.
So what's the difference and why does it matter?
I'm glad you asked!
When we breathe in, we can either breathe in through our nose or through our mouth. There might be situations when we are forced to breathe in through our mouth, for example if your nose is blocked, you are swimming, or you are doing intense physical activity. These situations naturally lend themselves to mouth breathing. However, our nose is designed to be the main channel for our breath and has evolved specifically for that purpose.
When we breathe in through our nose, some amazing things take place inside our nasal passages that have a profound effect on the air quality as it travels to the lungs and then into the blood stream. Inside the nose there are small hairs to filter and warm the air, a mucous lining to trap pathogens (i.e. viruses, bacteria, fungus and other nasties) and the sinuses release nasal nitric oxide. Recent research into what nasal nitric oxide does indicates that, among other things, this gas helps increase the capacity for our blood to take up oxygen and deliver it to our cells.
When we breathe through our mouths, none of the things that happen in our nose take place in our mouth. There is no filtration system, no warming the air and no nasal nitric oxide released. Essentially when you breathe through your mouth, it is as if your lungs are on the outside of your body and there is nothing protecting them.
It makes you wonder doesn't it? If your nose is designed to do all those things, why do we even breathe through our mouths? In answering this question, James Nestor, author of the book Breath - The New Science of a Lost Art, explains how over time, the influence of our diet and lifestyle has had a major impact on our ability to breathe through our noses. Interestingly, over the course of millennia, our bodies have undergone evolutionary changes as we move away from our natural way of being. Changes that came about as a result of farming meant that the foods we were eating were more processed and softer, and as a result, less chewing was required. Our mouths shrank, facial bones changed shape and our teeth became crooked, and all of this resulted in obstructions in airflow. If you know anyone who snores or who has sleep apnea, then you would know that these conditions are all linked to obstructions in the mouth.
So, how can we improve our breathing and become more natural nasal breathers?
I will be answering this question in my next blog post. Stay tuned to find out more.