Why Do Colds Strike When the Seasons Change? Your Nose Knows
The air has changed, morning and evening. And right on schedule, the scratchy throat and stuffy nose arrive. When we were young, a cold passed without much thought. After sixty, one cold can take a week — and the cough can linger for a month. We usually blame a weaker immune system. But researchers found another reason, and it is surprisingly simple: your nose gets cold. Your nose is the front door for viruses Most cold viruses enter through the nose. And the cells inside your nose do not just sit there. They constantly release tiny sacs called extracellular vesicles, which work as decoys. A virus mistakes a decoy for a real cell, latches onto it, and gets washed away in mucus instead of infecting you. Cold air changes this. In the study, just 15 minutes of exposure to cold air dropped the temperature inside the nose by about 5°C (9°F), and the release of those decoy sacs fell by nearly 42%. With fewer decoys, viruses reached the real cells far more easily — infections rose by up...