It’s a classic phrase as old as time: wet hair will give you a cold. Countless times over the course of my childhood, I can recall my mom or my grandma scolding me right after I hop out of a fresh shower before school, and rush to get changed and run out the door: “Don’t even think about leaving this house with wet hair, you’ll catch a cold!” Of course, this phrase stuck with me, as it has to many others over the course of time, and I’ve always been mindful to grab a blowdryer quickly before leaving the house with wet hair. However, I’ve often wondered, how accurate is this phrase? Is there truly a risk to leaving with wet hair and going outside of catching a common cold? I decided I needed to turn to research for the answer.
The Origin of a Cold
Traditionally, a “cold” is defined as a viral infection inherent in one’s nose and throat, otherwise known as the upper respiratory tract, that usually lasts over a period of about 10 days, and causes a number of symptoms including a weakened immune system, a runny or stuffy nose, a mucus-filled or inflamed throat, and heavy congestion (Mayoclinic.org). The beginnings of a cold are usually when a small invader known as a virus is transmitted through contact with the already ill, and is capable of latching onto the lining of your throat or nosecontact with the already ill, and is capable of latching onto the lining of your throat or nose (webmd.com). Eventually, as your white blood cells and immune system team up to destroy the virus, you are weakened, and your body’s defense takes a temporary hit. The cold is the cause of millions of sick days taken for school and work for adults and children alike as they take the time to rest, but especially children, who are at the highest risk of colds, and lose about 22 million school days a year due to this illness (webmd.com). In fact, webmd.com further states that Americans are estimated to have one billion colds annually, a shocking statistic.contact with the already ill, and is capable of latching onto the lining of your throat or nose (webmd.com). Eventually, as your white blood cells and immune system team up to destroy the virus, you are weakened, and your body’s defense takes a temporary hit. The cold is the cause of millions of sick days taken for school and work for adults and children alike as they take the time to rest, but especially children, who are at the highest risk of colds, and lose about 22 million school days a year due to this illness (webmd.com). In fact, webmd.com further states that Americans are estimated to have one billion colds annually, a shocking statistic.
So, now that we know what a cold is, let’s attempt to break down the causes of a common cold, and whether or not wet hair comes into play.
The Triggers: Does Wet Hair Come into Play?
According to Claudia Hammond, a contributing writer to BBC.com, cold or wet weather is in fact the most common cause of colds, due to studies in Germany and Argentina that have discovered a greater amount of colds in the winter, as well as in countries with traditionally hotter weather including Malaysia and Guinea, where colds are most common in the rainiest parts of the year. However, in addition to this, a common rebuttal is that winter is the most common time to catch a cold because most people choose to spend their time indoors, where they are in closer contact with other’s germs. In order to test this, a variety of experiments have taken place in lab settings in order to prove once and for all if cold and wet climates are to blame.
The most frequent experiments, as Hammond discusses, have been under controlled laboratory conditions in which experimental volunteers are exposed to the a cold virus under lowered temperatures. In a number of studies, the group exposed to the colder conditions more frequently contracted a cold, however, for the most part, results remained inconclusive. One study, however, offered a bit more insight and success into this question. The director of the Common Cold Centre in Cardiff, a part of the UK, decided to investigate whether the virus is triggered by being cold and wet (Hammond). In order to accurately investigate this question, he subjected his volunteers to, similarly, damp and cold conditions in the lab. However, where this experiment differed was that he instead sent them out into the real world to go about their daily lives, socializing with others who may or may not have the cold virus.
Included in this experiment, Eccles randomly assigned half of his people to sit with their feet in cold water for around twenty minutes, while half sat with their feet in an empty bowl for twenty minutes (Hammond). According to Hammond, while there was no difference between frequency and nature of cold systems after the first few days, four to five days following the experiment, twice as many subjects from the group that stuck their feet in the cold water had contracted the cold virus.
However, in another experiment conducted at Baylor University, 44 people were exposed to a cold virus, and randomly allocated half to stand in a cold room (Shape.com). However,they found that those who were exposed to colder conditions in the room were no more likely to contract the virus than those who were not (Shape.com).
So what all does this mean?
Of course, these results are all conflicting, and nothing is clearcut. In order to have a viable conclusion, there has to be a realistic way in which wet hair or chilled feet can give someone a cold. According to Hammond, one common theory involves the thought that the blood vessels that are responsible for dispersing white blood cells in a person’s throat and nose are constricted when your body is cold. Supposedly, once one’s hair dries and your body is warmed, the white blood cells are restored as they dilate and return to normal (Hammond). However, none of these results are concrete.
The overall conclusion I have reached through my research is that although there is no concrete study that proves that wet hair causes the cold virus, it could very much help the process along, as it affects the white blood vessels and their reaction time. So maybe, although the science isn’t one hundred percent in unison, it might be the right idea to listen to your mother, and wait until your hair dries before leaving the house.