The nose knows, folks.
While you can’t catch a cold from weather alone, temperature changes directly affect our susceptibility to sickness.
Cold, dry air increases our likelihood of catching something nasty — and our nasal passages are our first line of defense.
“The nasal apparatus is designed to be the first step in fighting off infection and filtering out irritants in the environment,” Dr. Amy Brown, a board-certified pulmonologist, assistant professor of pediatrics at New York Medical College School of Medicine, as well as an adjunct associate professor of public health at the School of Health Sciences and Practice, recently told HuffPost.
According to Brown, our noses have an internal humidification system that helps us adapt and respond to external environments — and it’s best to keep tabs on that as much as possible during cold months.
When the outside air is too dry, the nose must work overtime to humidify the air we breathe.
As Brown explains, “When nasal filtration and immune defenses aren’t functioning optimally due to dry air, viruses — like those that cause respiratory infections and fall colds — can get in more easily.”
Dry lips, nose, and skin indicate a dry indoor setting. A humidifier can help, but Brown warns that too much moisture in the home can make breathing difficult and promote mold growth.
She says the sweet spot for indoor humidity is 35% to 45%
In fact, experts say the key to prevention lies in maintaining your mucus layer.
A sheet of snot within the inner lining of the schnoz, the mucus layer, acts as a blockade for bacteria. This layer is critical as it removes airborne particles before they reach the lower airways.
Research shows that when a virus or bacteria enters the nose, it signals the cells lining the nose to replicate into decoy extracellular vesicles or EVS.
These EVs are like mini versions of cells specifically designed to protect the body from the threat of infection. As decoys, viruses stick to them instead of attaching to cells.
The nasal cavity also contains sickness-fighting cilia cells. Dr. Peter Filip, a rhinologist, told HuffPost that these are “microscopic finger-like projections which beat in unison [to] sweep mucus, bacteria and viruses away.”
Yet all of these snout defenses are compromised by cool air and dry nasal passages.
As The Post previously reported, researchers found that reducing the temperature inside the nose by just 9 degrees Fahrenheit kills nearly 50% of the billions of virus- and bacteria-fighting cells in the nostrils.
Humidity decreases alongside air temperature, making it harder for the mucus layer to function. This fluctuation coincides with the onset of cold season, which typically lasts from late August or early September to March or April. Flu season, meanwhile, generally runs from October to May.
Toddlers and preschool-aged children may have as many as 12 colds, respiratory infections, and/or stomach bugs a year.
While cooler climes are a major cause of nasal dryness, other lifestyle habits can also contribute. These include but are not limited to, dehydration, frequent nose picking, allergies, certain medications, autoimmune diseases, tobacco smoke and frequent introduction of foreign bodies like tissues and Q-tips into the nose.
Another culprit? Fragrances from candles and air fresheners.
“If there are excessive amounts of irritants or infectious particles in the environment, the nose has to work harder on filtration and may not keep up with promoting ideal humidification, which then leads to dryness,” Brown said.
Signs of a dry nose
- Soreness, irritation or congestion
- Thick mucus or dry yellow mucus
- Altered sense of smell
- Flaking skin, scabs or crusts within the nostrils or nasal cavity
- Itching or burning
- Nosebleeds
- Bloody scabbing in the nose
Experts agree that limiting exposure to dry air is the best way to keep your nasal passages at peak performance. According to Brown, “Ensuring appropriate ideal humidity in your indoor dwelling space is really the key for ongoing, long-term relief.”
See the Post’s picks for the best humidifiers on the market.
Folk can find further relief by visiting a steam room, staying hydrated, using saline-based nasal sprays and avoiding any scented items in the home.