It acts like a strong wall, guarding our health and preventing germs and dust from the outside world from invading our bodies.
Nose hairs play a crucial role in this line of defense, as they grow in the nasal cavity like a dense jungle, forming a natural barrier.
When the harmful dust tries to break through this line of defense, the mucus membrane on the nose hair will act like an experienced boxer, skillfully defusing the threat of these intruders.
It binds these dust and bacteria tightly in the nasal cavity through adsorption and adhesion, preventing them from entering our lungs.
In our daily life, some people may find that their nose hair is very long, even to the point of "scurrying" out of the nostrils. However, most people don't grow nose hair to this extent. Why is that? 
1. Nose hair can block dust, bacteria, etc. in the air, so that the human body can inhale the filtered clean air, this filtering effect helps to prevent harmful substances from entering the nose and respiratory tract, thereby preventing respiratory diseases, nose hair can completely block large particles greater than PM 50.
2. Nose hair can maintain the temperature of the nasal mucosa, prevent the cold air from the outside from being directly inhaled into the trachea, and also keep the nasal mucosa moist, which has the effect of preventing dry or atrophic rhinitis and nosebleeds.
3. Nose hair can also maintain the olfactory nerve from damage, so that the nose can smell various odors, and transmit the aroma of food to the brain to increase appetite. When larger foreign substances are inhaled into the nose, nasal hairs carry stimuli to the brain and expel them from the body in the form of sneezing.
Nasal inflammation
When the nasal cavity is stimulated by infection or allergies, it can cause swelling and inflammation of the nasal mucosa, which can lead to rapid or irregular growth of nasal hair, which is easy to escape out of the nasal cavity.
In addition, nasal inflammation can also cause dryness, itching, and discomfort in the nasal passages, which can further exacerbate nose hair picking.
In order to solve this problem, nasal inflammation is first required, which can be relieved by allergy medications, anti-inflammatory drugs, or nasal sprays, etc. Androgen secretion is vigorous
There are several reasons why nose hair can come out, one of which is related to the exuberant secretion of androgens, a type of male hormone that plays an important role in the development and function of the body.
When male androgen secretion is vigorous, there are some physiological changes in the body, one of which is the increase in hair, including nose hair.
Therefore, for some men, if they find that their nose hair is often popping out, it may be due to excessive androgen production.
Environmental factors
Airborne pollutants and dust particles can stimulate nose hair growth, making it thick and long. In addition, strong sunlight and ultraviolet radiation may also have an effect on nose hair, making it grow more vigorously. In addition to environmental factors, nose hair protrusion may also be related to personal lifestyle habits. For example, bad habits such as long-term smoking, drinking, and eating spicy foods can stimulate nose hair growth.
In order to control the growth of nose hair, there are some measures that can be taken, which can keep the indoor air fresh, clean the air conditioner filter regularly, and reduce indoor dust and pollutants. Secondly, you can wear a mask or use a nose hair trimmer to trim excessively long nose hair when you go out.
Pick your nostrils with your hands
When we pick our nostrils with our hands, it stimulates the hair follicles in the nasal cavity, causing the growth of nasal hair to accelerate, making it easier to escape. In addition, picking the nostrils can damage the hair follicles of the nose hair, causing the nose hair to become soft, curved, or even fall out.
In order to keep the nose hair healthy and neat, we should avoid picking the nostrils with our hands, and when the nasal passages feel uncomfortable, we can use a soft tissue or cotton swab to gently wipe them to keep the nasal passages clear.
In addition, we can also control the length of the nose hair by trimming it so that it remains at the right length and does not affect the image or health.
In the face of these unwelcome "little guests", many people will subconsciously think of a simple way - directly pluck it out with their hands, however, is it really appropriate to do so?
Nasal hairs are the first line of defense of the respiratory system, they can protect our respiratory system by blocking harmful substances such as dust and bacteria in the air from entering the nasal passages.
In addition, nose hair can also maintain the humidity in the nasal cavity and prevent nasal dryness, so plucking out nose hair will not only weaken our respiratory defense, but may also cause problems such as nasal dryness and bleeding.
Secondly, there are also health hazards in plucking nose hair by hand, there are a lot of bacteria on our fingers, and plucking nose hair directly with our hands may lead to bacterial infection and cause nasal inflammation.
Nutritional deficiencies
Nutritional deficiencies do have an impact on nose hair, causing it to turn white, and this is because nose hair, like any other hair, needs adequate nutrients to maintain its healthy color and texture.
When the body lacks essential nutrients, such as vitamins, minerals, and proteins, the hair loses its original pigment, resulting in graying of the nose hair.
In the case of nutrient deficiencies, the whitening of the nose hair is usually a gradual process, at first, the nose hair may only appear a few small white spots, and as the nutrient deficiency continues, these white spots will gradually expand, eventually causing the entire nose hair to turn white. Genetic factors
Genetic factors play an important role in the process of turning nose hair white, and characteristics such as color and growth rate of nose hair, which are part of human hair, are genetically influenced.
Some people are born with a lighter hair color, while others have a darker hair color.
Similarly, if a person has a genetic history of graying nose hair in their family, then the person is also more likely to have graying nose hair.
Disease effects
The influence of age factors on nose hair color really cannot be ignored, and with the passage of time, the whitening of nose hair has become a common experience for many people, and the reason behind this is mainly related to the decrease in melanocytes during aging.
Melanocytes play a key role in our hair and hair, they produce pigment and provide color to the hair.
However, as we age, the number of these cells decreases, resulting in a lighter color of nose hair, which is especially noticeable in many older people, who tend to appear white or grayish-white.
Age factor
Chronic diseases such as diabetes and adrenal insufficiency can cause nasal hair to turn gray due to a lack of nutrients and oxygen**.
In addition, some psychological stress and emotional factors may also have an impact on nose hair color. For example, people who are chronically anxious, nervous, or depressed may have an increased risk of graying their nose hair.
In addition to disease and psychological factors, genetics are also an important factor in the color of nose hair, some people are born with lighter nose hair, while others are not. In addition, nose hair also gradually turns white with age, which is due to the decrease in melanocytes in the hair follicles with age. 
Trim your nose hair
Use a special nose hair trimmer or round-tipped scissors to carefully trim off the nose hair that shows your nostrils, make sure the tool is clean and hygienic before trimming to avoid infection, and be cautious when trimming to avoid over-trimming that will cause the nose hair to be too short and affect its function.
Laser hair removal
If you find that nose hair trimming is troublesome or ineffective, you can consider going to the aesthetic department of the hospital to remove the nose hair at the entrance of the nostrils using laser hair removal.
Laser hair removal is a safe and effective method to precisely remove specific areas of hair without damaging the surrounding hair**.
Keep your nasal passages clean and hygienic
Clean your nasal passages regularly to avoid the accumulation of dirt and bacteria. It can be washed with saline or a medical nasal wash. At the same time, avoid picking your nostrils with your fingers so as not to damage the nasal mucosa and nose hair.
Avoid over-cleaning
While it's important to keep your nasal passages clean, excessive cleaning can damage your nose hair and mucous membranes, accelerating your nose hair turning white, so do it in moderation and avoid using too violent or frequent ways when cleaning your nasal passages.
Maintain good health
Maintaining a sensible diet, moderate exercise, and adequate rest can help boost immunity and reduce the risk of disease, thereby slowing down the rate at which nose hair turns gray.
Take care to moisturize
Keeping your nasal passages moist helps maintain the normal function of your nose hairs and slows down the process of your nose hair turning white, you can keep your nasal passages moist by drinking plenty of water, using moisturizers or lubricants, and in dry seasons or environments, you can use a humidifier to increase indoor humidity to help keep your nasal passages moist.
Smell disorders
There are cells in the nose called olfactory cells, which are responsible for olfactory function, if the olfactory cells are abnormal or damaged, then we may have olfactory disorders, that is, the inability to smell certain odors, which may be caused by nose cancer, lung cancer, breast cancer, etc.
Therefore, if you find that you suddenly can't smell certain scents, or your sense of smell is not as sensitive as before, then you need to be alert to the possibility of cancer.
There is a change in the appearance of the nose
For example, the nose may be deformed, asymmetrical, or lumpy, which may be caused by the growth of a nasal tumor, and if you notice that you have these changes in your nose, you should also be alert to the possibility of cancer.
Bleeding may occur in the nasal cavity
This condition can be caused by diseases such as nasopharyngeal cancer, nasal cavity cancer, etc., and if you find that you are bleeding in your nasal cavity, then you also need to be alert to the possibility of cancer.