Rediscovering the importance of nasal breathing in sleep or, shut your mouth and save your sleep.

Recent research, stimulated by the growing awareness of the sleep apnea syndrome, has shown that nasal breathing plays a major role in the regulation of respiration in sleep. These observations are not new; they confirm century-old clinical findings on the importance of nasal breathing in sleep. The earliest account of the deleterious effects of mouth breathing in sleep was made by Lemnious Levinus towards the end of the sixteenth century. Two hundred years later, Catlin dedicated an entire book to the superiority of nasal breathing over mouth breathing in sleep; and in the late 1800's, Cline, Wells, Griffin and others showed that obstructed nasal breathing causes sleep disorders.