Why are we more likely to get sick if we are cold?

Bundle up! Our cells' ability to fend off infection is suppressed when they are below body temperature.

Asked by: Emre Yorgancigil, Turkey

It’s partly because everyone stays indoors when the weather is bad, which helps germs to spread. But a 2014 study at Yale University found that the rhinovirus that causes most colds can only infect cells that are slightly below body temperature. Warm cells are able to fend off the virus by producing lots of interferon proteins. In cold air, the lining of your nose gets chillier and the cells’ immune response is much weaker.

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