The Oxygen Advantage: The Simple, Scientifically Proven Breathing Techniques for a Healthier, Slimmer, Faster, and Fitter You

by Patrick McKeown

Mouth breathing influences asthma in a number of ways: • Air taken in through the mouth is not filtered of airborne particles, including germs and bacteria. • The mouth is simply not as effective as the nose in conditioning air to the correct temperature and humidity prior to entering the lungs. • Because the mouth provides a larger space to breathe through than the nose, breathing volume will be higher, causing too much carbon dioxide to be expelled from the lungs. Carbon dioxide is a natural “opener” of the smooth muscle in the airways. The loss of carbon dioxide therefore causes asthma airways to narrow even more. • Unlike nasal breathing, mouth breathing does not allow us to benefit from nasal nitric oxide, which supports the lung’s defensive capabilities. Taking all these factors into consideration, it is not surprising that mouth breathing causes a reduction in lung function in people with mild asthma and plays a significant role in the exacerbation of asthma symptoms.