Wet Hair: What It Means For Your Health

Written by: Yeira Wong

Even before the COVID-19 pandemic, every time I left the house with wet hair, my mom would scold me for not leaving enough time to blow dry it because she firmly believed that being in the cold with wet hair would me sick. Similarly, I would also get in trouble for sleeping with wet or damp hair because she thought it would also make me sick or give me potential headaches. To be completely honest, I am not sure what the effects of having wet hair is on my health in these situations, but I’m not sure if she’s entirely right, hence I will be delving deeper into the topic. So, if you’re also interested in knowing, keep reading!

How we get the common cold in very simple terms

The best place to start is to identify how one can catch the common cold. Rhinoviruses are known for causing colds and cold-like diseases. They are directly spread through person-to person contact through infected droplets or aerosols in the air. The droplets are spread through sneezes or coughs of someone who is sick or carries the sickness. The virus then spreads through the nasal passage into the upper respiratory tract and into the rest of the body. Research has been done to prove that body temperature or temperatures in general can have an impact on the virus’s replication as rhinoviruses seem to replicate better at temperatures lower than 37°. Hence, the belief of wet hair and its correlation to getting sick can be blamed on that as it will make you feel colder, because you lose heat from your head.

What happens when you’re cold?

When the body is cold the skin sends a message to the brain about the skin temperature and the rate of change in said temperature. The brain communicates with the nervous system to both control the temperature as well as where the blood should go, and when to induce shivering. It helps lower the body temperature to conserve energy but can also cause hypothermia if the temperature drops too much. At this time, most of the blood is directed to the internal organs to maintain a stable core temperature, so the blood doesn’t travel to the cold skin as much. Shivering is caused when the muscles tighten and relax rapidly, back, and forth, trying to warm up your body. It can warm you up for a while, but over time you will run out of fuel or sugar and be too tired to maintain your body temperature in that way.

Why can the cold weather or temperature around us be bad for us? Well, it can lead to people spending more time indoors, reducing sun exposure, and vitamin D intake which can affect the immune system. Spending more time indoors can also lead to more transmission of disease as people are in a closed space more often with poorer circulation. As mentioned, being cold can lead to hypothermia which can make you more likely to contract other infections with a weakened immune system. It can also cause other effects such as constricting blood vessels that carry white blood cells contributing to a lowered immune defense against other infections.

Sleeping with wet hair

There is no actual evidence that having wet hair can cause colds, as colds are contracted through contact with a virus. However, it can cause fungal infections as moisture and warmth are ideal for fungi.  Because of this is can also worse asthma symptoms and affect those with weakened immune systems. Additionally, sleeping with wet hair can also cause damage to your hair as your hair is weakest when it is wet and susceptible to breakage.

Contrary to popular belief, having wet hair outside in the cold or sleeping with wet hair does not cause the sickness, but can potentially increase the rick on getting it. However, it can have other effects on the body. It can lower our body temperature causing you to feel colder and sneeze more, making it seem as though you are getting close to being sick, while not actually being sick. Overall, wet hair is not really a cause for concern, whether it be going out in the cold, or sleeping. It may not be the best idea, as it can have other implications, but it is not the cause for a cold. To prevent getting sick, proper hygiene, like washing hands often is a probably a better way to go than agonizing over one’s state of hair.