A new wave of understanding about a common health oddity is sweeping the nation, bringing relief to many who have long wondered: why can you only breathe through one nostril when you’re sick?
Story Highlights
- The nasal cycle causes alternating nostril congestion, a normal physiological process.
- Illness amplifies the nasal cycle, making one nostril feel more congested.
- The phenomenon is harmless unless persistent, which may indicate a medical issue.
- Experts emphasize the importance of distinguishing between normal and pathological symptoms.
The Nasal Cycle: A Natural Process
The nasal cycle is a natural, physiological process where nostrils alternate congestion and decongestion. This cycle, documented as early as the 19th century, is controlled by the autonomic nervous system and typically goes unnoticed in healthy individuals. During illness, however, inflammation and mucus build-up make this cycle more apparent, leading many to feel as though one nostril is more congested than the other.
Experts explain that this cycle is part of a body’s natural defense mechanism. Increased blood flow to the turbinates, the structures within the nose that regulate airflow, is a normal response aimed at trapping pathogens and preventing them from entering the respiratory system. This process highlights the human body’s intricate design, but it can also lead to discomfort during respiratory illnesses.
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Understanding Illness Amplification
During a cold or flu, the nasal cycle becomes more pronounced due to the added congestion from mucus and swelling. This often leads to the perception that one nostril is blocked while the other is clear. According to Dr. Rachel Roditi from Brigham and Women’s Hospital, the illness amplifies the nasal cycle, making it more noticeable to individuals. This amplified effect is particularly evident in about 80% of the population, who experience this phenomenon unconsciously.
Dr. Masayoshi Takashima of Houston Methodist adds that while this is generally harmless, persistent unilateral nasal congestion should be evaluated by a healthcare professional. Conditions such as a deviated septum or nasal polyps might require medical intervention if symptoms persist beyond the illness period.
Doctors Explain Why You Can Only Breathe Through One Nostril When You're Sick | @scoopit https://t.co/of2euweUag
— Enzo Calamo (@EnzoCalamo) December 31, 2025
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When to Seek Medical Attention
While the nasal cycle is a natural occurrence, it’s crucial to recognize when symptoms might indicate a more serious issue. Persistent or severe congestion that does not resolve with decongestants or after the illness subsides could point to structural problems within the nasal passages. Conditions like a deviated septum, chronic sinusitis, or nasal tumors could be underlying causes, and consulting an Ear, Nose, and Throat (ENT) specialist is advisable in such cases.
ENT specialists play a crucial role in distinguishing between benign and pathological causes of nasal congestion. They provide guidance on treatment options, which may include medication, lifestyle adjustments, or in some cases, surgical intervention to correct structural issues. Awareness and education about the nasal cycle can help alleviate unnecessary concerns and guide individuals towards appropriate medical care when needed.
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Sources:
Medical News Today: Why Can I Only Breathe Through One Nostril?
Men’s Health: Understanding the Nasal Cycle During Illness
UTMB: Little Known Nose Facts Podcast
Cleveland Clinic: Nasal Cycle and Congestion Explained
