The real reason you're more likely to get ill in the winter

The colder it gets, the more prone you are to getting ill. You’re advised to take a flu shot – and in this Covid-19 era, having your boosters up to date – wear protective clothing to keep warm. A new research that explores the actual link between lower temperatures and illness.

The colder, the sicker

Scientists at the Mass Eye and Ear hospital and Northeastern University in America have found that the cold air itself damages the immune response occurring in the nose. The findings suggest that the newly discovered immune response inside the nose is suppressed by colder temperatures, and the illnesses are not more common simply because people are stuck indoors. Rhinologist and lead author of the study, Dr. Benjamin Bleier said:

Cold air is associated with increased viral infection because you’ve essentially lost half of your immunity just by that small drop in temperature.

The study, published in the Journal of Allergy and Clinical Immunology, found that reducing the temperature inside the nose by as little as 5 degrees Celsius kills nearly 50% of the billions of virus and bacteria-fighting cells in the nostrils.

How it compares to previous studies

The findings of this research dispute the conventional belief that cold and flu season occurred in cooler months because people are stuck indoors more where airborne viruses could spread more easily. However, Dr Bleier said that’s not exactly the case:

Our study however points to a biological root cause for the seasonal variation in upper respiratory viral infections we see each year, most recently demonstrated throughout the Covid-19 pandemic.

Sources used:

CNN: Scientists finally know why people get more colds and flu in winter

The Independent: Revealed: The reason why colds surge when temperatures drop