The sensation that one nostril is more blocked than the other throughout the day is a natural and normal phenomenon called the nasal cycle. If the discomfort is constant or leads to mouth breathing, it is advisable to consult a specialist.

noli's read

Dr. NEVER describes here a self-regulation phenomenon that is quite real and has been documented since the end of the 19th century: the nasal cycle, characterized by a natural alternation of airflow between the two nostrils. According to a reference scientific review published by Pendolino et al. in 2018 (a comprehensive literature review), this mechanism allows the nose to optimally humidify and filter the air by letting one side rest. This phenomenon, managed by our internal balance, generally goes unnoticed in daily life for the majority of us. The claim that many people are "mistaken" in believing they have a stuffy nose is, however, slightly exaggerated. Indeed, if one feels marked respiratory discomfort on one side, it often signals increased sensitivity or a slight misalignment of the airways that makes this natural cycle noticeable. Nevertheless, his final invitation to seek out a specialist in cases of constant mouth breathing or permanent blockage is an excellent reflex for regaining smooth breathing.

the sources

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