Once again, your grandma was right (you eat your vegetables, right?). She might just have said "it's cold outside, you'll catch a cold" while the recent study published in theProceedings of the National Academy of Sciences phrases it a bit differently ("Temperature-dependent innate defense against the common cold virus limits viral replication at warm temperature in mouse airway cells"), but the general idea is the same.
Rhinovirus, which is the most frequent cause of the common cold and "asthma exacerbations", can reproduce better at the lower temperatures found in a nose cavity compared to the warmer temperature found in lungs. It appears that this is because the body's immune system is less effective at cooler temperatures, thus giving the virus more leeway to get a toehold and, eventually, overrun our system.
Read more: http://www.treehugger.com/health/grandma-was-right-common-cold-virus-prefers-cold-noses-new-study-shows.html
