Would you believe me if I told you 85% of humans only breathe out of one nostril at a time. Well its true and even more interesting is that the pattern of switching from breathing out of one nostril to the other happens in a cyclical fashion, with about four hours or so between each switch typically, this can vary from person to person and vary based on your body position or nasal congestion.
The first known instance of someone studying this ‘nasal cycle’ was a German nose specialist named Richard Kayser in 1895. The way your nose is able to accomplish the switch is by the erectile tissue which will swell up in one nostril causing it to be mostly blocked, while the erectile tissue in the opposite nostril will shrink making it open and able to breathe through. Even more interestingly, well to me, is that depending on which nostril you are predominately breathing through at any moment will affect your body and brain.
For instance a study in 1988 showed that breathing through your right nostril significantly increases blood glucose levels while breathing through your left nostril will give you the opposite effect, it is speculated from this that abnormal nasal cycles such as breathing through your right nostril for many years without switching could be a contributing factor in certain cases of diabetes. Most interestingly of all is that another study published in 1944 showed that when breathing through your left nostril it will make your right hemisphere more active and vice versa. Who would of thought that depending on which nostril you breathe through could have such a massive effect on your body.