Beyond Sniffing: Exploring the Multifaceted World of Nasal Functions, from Filtering to Snot Science

Our noses, often overlooked until disease alters their functionality, perform crucial tasks in our daily lives. Apart from the obvious sense of smell, they serve as vital air conditioners and filters, regulating the temperature and humidity of the air we breathe while safeguarding against unwanted particles and viruses.

The nose’s anatomy is far more intricate than meets the eye. Extending upwards and backwards from the nostrils, dual cavities house bony folds known as turbinates, increasing the nasal cavity’s surface area to an impressive 150 square centimeters, enabling efficient filtration and air conditioning. Turbulence caused by these turbinates ensures that approximately 80 percent of suspended particles collide with the nasal cavity’s skin, effectively filtering them out.

Beneath the mucosa, the lining of the nose, lies a highly vascularized region that serves as a heat exchanger. This area, controlled by nerves, can rapidly adjust blood vessel dilation or constriction, modulating heat exchange. Additionally, the nasal cavity is connected to several cavities through narrow tubes. These include four sets of sinuses in the facial bones and the middle ear cavity.

The Eustachian tubes, connecting the middle ear cavity to the back of the lower nose, play a crucial role in equalizing pressure. Normally closed at rest, they open when there is a difference in pressure between the middle ear and the outside environment, causing a “popping” sensation. Other sounds, such as squeaks or crackles, may occur due to the opening and closing of inflamed tubes during activities like swallowing. Congestion in the nose can lead to blocked tubes, resulting in pain from pressure buildup.

Despite their importance, the exact purpose of sinuses remains unknown. One theory suggests that they evolved to accommodate larger facial structures without excessively weighing down the head. Furthermore, paranasal sinuses‘ lining cells produce nitrous oxide, a compound inhibiting viral and bacterial growth, thereby bolstering our immune defenses.

Now, let’s delve into the fascinating realm of mucus. The upper respiratory tract’s major passages are lined with a mucous membrane containing goblet cells responsible for producing mucus. Besides humidifying the air we inhale, mucus captures small particles like pollen or smoke. Cilia, hair-like structures within the mucous membrane, transport trapped particles out of the nose. Beating at a remarkable frequency of ten to 12 times per second, the cilia propel mucus at a rate of one millimeter per minute.

Composed of approximately 95 percent water, 3 percent proteins (including mucin and antibodies), and 1 percent salt, among other substances, mucus forms a sticky, elastic gel through crosslinking of mucus strands. Throughout the day (with reduced production during sleep), our noses produce over 100 milliliters of this gelatinous substance, carrying dead cells, dust, and debris to the stomach for recycling.

Mucus plays a crucial role in combating infections. It carries white blood cells and antibodies, increasing in volume to eliminate infections, irritants, or allergens. Watery mucus, as seen in allergies or during the initial stages of a viral infection, tends to exit via the nostrils, resulting in a “runny nose.” Conversely, thicker mucus typically drains down the back of the nasal cavity into the throat, aided by the cilia’s movement.

The various colors of mucus can trigger concern. Orange or brown hues may indicate the presence of blood, while yellow and green shades result from white blood cells engaged in fighting bacterial and viral infections. The intensity of colors tends to amplify the longer the mucus remains in the nasal cavity, meaning that morning nose blows often yield more vibrant hues compared to later in the day.

Contrary to popular belief, green mucus does not necessarily signify a bacterial infection that warrants antibiotic treatment. Most upper respiratory tract infections, even those accompanied by green mucus, resolve with or without antibiotics. Research consistently shows that around 80 percent of sinus infection patients recover without antibiotics within seven days, compared to 90 percent with antibiotics.

When seeking relief from symptoms associated with colds, flu, or upper respiratory tract infections, nasal sprays prove effective while minimizing side effects. Decongestant sprays are the optimal choice for treating nasal congestion resulting from acute viral infections and can be safely used for at least seven days. By constricting swollen blood vessels and reducing excessive mucus production, these sprays alleviate congestion. However, they can also slow down cilia activity, impeding mucus clearance and causing stickiness. Regular use of saline solutions or sprays aids in washing away mucus and stimulating more efficient cilia movement.

For allergic rhinitis, controlling symptoms may require oral antihistamines and/or nasal steroid sprays. Adding a saline nose spray to steroid sprays enhances their effectiveness by flushing away allergens and mucus.

Now, let’s explore the correct technique for using nasal spray, as it’s not as straightforward as it may seem. Follow these steps for optimal results:

1. Maintain an upright position with a slight forward tilt of the head.
2. Hold the nasal spray bottle with your thumb at the base and your index and middle fingers on top.
3. Insert the spray bottle’s tip into one nostril, gently blocking the other nostril with your other hand.
4. Squeeze the pump using your index and middle fingers while breathing in slowly, ensuring the medication remains in place.
5. Use your right hand to deliver a spray into the left nostril, directing it toward the left ear. Repeat the process on the other side.

With these insights into the complexities of nasal functions, we gain a deeper appreciation for their significance in our daily lives and the importance of proper care and treatment.