Do you increase your risk of becoming ill by going outside into the cold with a wet head? This would seem like an old wives' tale... how could the cold weather make you ill? The only "logic" I can see is that this would lower your body temperature (from the water evaporating off your head) and this would lower your resistance to infection.
— Cold and wet
Dear Cold and wet,
A grandparent of yours may perpetuate this common myth, however research has shown that viruses, not exposure to cold temperatures, cause colds. Having a wet head actually has no effect on whether or not one gets a cold or flu. Scientists from the National Institute of Allergy and Infectious Diseases (NIAID), a division of the National Institutes of Health, have shown that exposure to cold temperatures does not influence the development or severity of a cold. This means that if a person is exposed to a cold virus but isn't necessarily showing symptoms, exposure to cold temperature doesn't make a difference as to whether this person gets sick or how sick this person will become.
Still, most colds occur during the fall and winter months, when schools begin to open and the mercury begins to fall. While cold temperatures do not cause colds, the colder months of the year are more conducive to infection or transmission of the cold and flu viruses. Researchers have actually learned that low-humidity and cold air conditions are the ideal transmission conditions for these viruses. What's more, dry air can dry the mucous lining of the nasal passages, making it more open to viral infection. Finally, young people typically are in school during the cold months; having students (and their families) in such close contact provides a great network for the cold and/or flu to traverse.
As you can see, there are number of reasons cold and flu season occurs in the colder months. However, it seems that stepping straight from the shower into a blizzard, while a great way to get frost bite on some tender parts (if you stay out long enough), is not actually enough to make you sick.Alice!