Nasal breathing
You take thousands of breaths a day, and most of them can go through your nose. The nose is not just a hole for air. It cleans, warms, and moistens each breath before it reaches your lungs. This page explains what the nose does, why people breathe through the mouth, and when it is worth asking a doctor.
What your nose does with each breath
Inside the nose are curved shelves of tissue with a rich blood supply. As air passes over them, it is warmed and moistened. A thin layer of mucus catches dust and germs, and tiny hairs sweep it away. By the time air reaches your lungs, it has been cleaned and conditioned. Your nose is also how you smell, which is part of how you taste food.
The nasal cycle
If one side of your nose feels more open than the other, that is usually normal. The two sides take turns being a little more open over the day. Most people never notice it unless they have a cold.
Why people breathe through the mouth
Mouth breathing is common during hard exercise, when talking, and when the nose is blocked by a cold or allergies. That is fine. The body is built to use both routes. It is worth paying attention when the nose feels blocked most of the time, or when mouth breathing happens every night during sleep.
Sleep, snoring, and the nose
Loud snoring, gasping, or pauses in breathing during sleep can be signs of sleep apnea. That needs a doctor, not a home fix. You may have seen people online taping their mouths shut at night. Researchers who reviewed the studies found a possible risk of serious harm, especially for people with a blocked nose. Please do not try it, and never on a child.
A gentle practice
On an easy walk or while sitting quietly, notice your breath. If it is comfortable, breathe in and out through your nose for a minute or two, slow and relaxed. Stop if you feel short of breath, and breathe however feels natural. This is a way to notice your body, not a treatment.
When to see a doctor
Talk with a doctor if your nose is blocked most days, if you often get nosebleeds or sinus pain, if a child snores most nights, or if anyone in your home snores loudly, gasps, or seems very tired during the day. If breathing is suddenly hard, use your local emergency number.
This is general information. For your own health, talk to a doctor.