Nasal health is the "barometer" of human health. As the gateway of the respiratory system, the nasal cavity is the first line of defense for air purification and the "source" of various diseases. However, many seemingly insignificant "little habits" related to the nose in daily life, such as frequent nose picking, forcefully blowing nose, and randomly pulling out nose hair, may affect health. April 12th is National Nose Day, and a reporter from Science and Technology Daily interviewed relevant experts to interpret the potential risks and protective measures of nasal health from multiple perspectives. The role of the nose is very important, "said Zhong Cheng, director of the Department of Otolaryngology at Southwest Hospital of Army Medical University." Although the nose is small, it carries important functions such as breathing, smell, and immunity. The mucosal area lining the nasal cavity of an adult ranges from approximately 120 square centimeters to 150 square centimeters. A healthy nasal cavity is a sophisticated 'air handling system'. Before air enters the lungs, about 80% of particles with a diameter greater than 5 microns can be filtered out through the nasal cavity Feng Dandan, the attending physician of the Otolaryngology Department at the Army Medical University Army Characteristic Medical Center (Daping Hospital), said that the nose is roughly divided into the outer nose, nasal cavity, and sinuses, among which the nasal cavity structure is the most complex. The nasal cavity includes nasal turbinates, mucosa, epithelial cells, etc. It is divided into left and right chambers by the nasal septum, with the front connected to the outside through the nostrils and the back connected to the nasopharynx. The wider part of the anterior lower part of the nasal cavity is the nasal vestibule. The nasal vestibule is mainly located on the inner surface of the nasal wing and tip, lined with skin and covered with nasal hair. It has the function of filtering dust and purifying inhaled air. Nasal hair is the first line of defense for air entering the nasal cavity, acting like a natural filter that can block larger particles and dust in the air. The nasal cavity is covered with mucous membrane, which can regulate appropriate temperature and humidity, creating an ideal gas environment for the lower respiratory tract. The secretion produced by mucous membranes is the "epidemic prevention shield", which contains immune substances such as lysozyme and interferon, which can kill some bacteria and viruses. The blood vessels beneath the mucosa are extremely abundant, including arteries, veins, capillaries, etc., interwoven into a network that extends in all directions. Among them, the nasal turbinate mucosa, which belongs to the nasal cavity structure, is like a humidifier, and there is a rich vascular network inside the nasal turbinate mucosa. Abnormal nasal cavity can easily trigger a chain reaction. The health status of the nasal cavity is closely related to multiple systems throughout the body, and Zhong Cheng uses the "domino effect" to describe its harm. Abnormal nasal cavity can trigger a chain reaction of overall health Feng Dandan said that as the "gatekeeper" of the respiratory system, if the nasal mucosa is damaged or its function declines, bacteria are more likely to drive straight in, increasing the risk of respiratory infections and causing diseases such as colds, pharyngitis, and bronchitis. In addition, the nasal cavity is connected to the ears and throat, and nasal problems may affect adjacent organs, such as causing otitis media, pharyngitis, etc. Chronic rhinitis and other factors can lead to nasal turbinate hypertrophy, deviated nasal septum, sinusitis, nasal polyps, and other nasal diseases. These nasal diseases may cause nasal congestion, and long-term nasal congestion not only leads to sleep breathing disorders, affects blood oxygen supply, increases the risk of chronic diseases such as hypertension and heart disease, but also affects facial appearance. Once nasal congestion becomes severe, people will be forced to use their mouth to breathe. Zhong Cheng said that if the respiratory airflow passes through the mouth and exceeds a certain proportion (usually 25% -30%) for a long time, it can cause major problems. Long term open mouth breathing can lead to insufficient lip muscle strength and difficulty closing the lips. Even if the cause of nasal breathing obstruction is removed, patients often maintain their original oral breathing habits and find it difficult to improve on their own Xiong Yu, director of the Department of Stomatology at Southwest Hospital, stated that many people mistakenly believe that breathing through their mouths is just a matter of habit, but little do they know that this can lead to "adenoid facial features" over time, manifested as mandibular retraction, misaligned teeth, outward lip thickness, and even affect children's craniofacial development. These patients often have abnormal bite function and require orthodontic or orthognathic surgery for correction. In addition, various pathological conditions of the nasal cavity may also lead to olfactory dysfunction. Long term nasal congestion in adults may be associated with an increased risk of Alzheimer's disease - hypoxia accelerates brain cell apoptosis, leading to memory loss. Developing good nose care habits in daily life may seem harmless, but it can cause significant harm. Many people like to pick their nose. But picking the nose not only damages the nasal mucosa, but may also introduce pathogenic bacteria into the nasal cavity. When digging the nose with fingers, bacteria on the fingers can be carried into the nasal cavity, which can easily cause nasal infections. In addition, if the nose becomes red, swollen, and acne is compressed, the infection may flow back to the skull through facial veins, and in severe cases, it may even cause cavernous sinus thrombophlebitis Zhong Cheng said. Clinical data shows that incorrect blowing of the nose can lead to damage to the nasal mucosa. Zhong Cheng pointed out that repeated digging can easily cause dryness and damage to the nasal mucosa, increasing the probability of allergic reactions; Forcefully pinching both nostrils while blowing can easily cause local swelling, blockage, and pain in the nostrils; Excessive force on the nose can also cause acute or chronic inflammation of the nasal mucosa, and even lead to nosebleeds or infections. Regarding this, Zhong Cheng stated that the correct approach is to alternate blowing your nose on one side, that is, holding down one nostril while slowly exhaling and expelling secretions on the other side, alternating between the two sides to allow the nose to flow naturally. To avoid excessive force and prevent secretions from flowing back into the middle ear or sinuses and causing infection. Many nasal diseases may initially be minor issues, but if ignored for a long time, they will gradually worsen. Developing good nasal care habits in daily life is more important than treating the illness after it has occurred Feng Dandan stated that long-term rubbing of the nose may lead to sensitivity of the skin around the nose and trigger contact dermatitis; Wearing a mask for a long time may lead to hypoxia of the nasal mucosa due to insufficient air circulation, resulting in discomfort such as dryness and stinging; Frequent removal of nasal hair can weaken the filtering function of the nasal cavity and increase the risk of respiratory infections. Feng Dandan reminded that the nasal cavity should not be dug by hand in daily cleaning, and it can be gently washed with physiological saline spray or nasal washer; During the dry season, a small amount of Vaseline or vitamin E ointment can be applied to the nasal vestibule to prevent dryness and cracking of the nasal cavity. In addition, it is also possible to supplement vitamin A in moderation C、E， Promote nasal mucosal repair; Persist in moderate exercise, including jogging, swimming, etc., to improve nasal blood circulation. Early symptoms of nasal diseases are insidious and easily overlooked. It is recommended to undergo nasal endoscopy at least once a year, especially for individuals with a history of allergies or family genetics Zhong Cheng said. (New Society)