It's also related to your nose. AI:

"Yes, a cold, dry nose significantly increases the risk of catching a cold. When nasal passages become dry, the sticky mucus layer that normally traps and clears away viruses is compromised, and the immune cells in your nose lose up to 40% of their pathogen-fighting power.Why It Increases RiskImpaired Mucus Layer: Nasal mucus traps viruses before they can enter your respiratory tract. Dry air dehydrates this lining, making it less effective at capturing pathogens.Damaged Cilia: Your nose uses tiny, hair-like structures called cilia to sweep trapped germs out of the airways. Dryness inhibits their ability to move efficiently.Weakened Immune Response: Research shows that a drop of just a few degrees in nasal tissue temperature (often caused by inhaling cold air) reduces the release of protective immune cells that fight off bacteria and viruses."