Does Being Cold Really Give You a Cold?

             As the weather gets colder there is always a phrase you can count on hearing “Put on a coat or you'll catch a cold.” It's a belief that parents and grandparents alike seem to pass on to the next generation. But have you ever wondered if there is any truth to this “old wives tale” that not wearing a coat in the cold really increases your chances of catching a cold? This belief comes from the idea that cold weather can directly cause a virus when in reality that’s not true. According to the CDC one of the most common types of viruses are rhinoviruses. Rhinoviruses are a respiratory virus that spreads through droplets of an infected person when they cough or sneeze. The cold and dry air can often lead to more frequent coughing and sneezing, which increases the frequency of potential viral spread instances. The idea that exposure to cold weather and environments (especially without a coat) can lead to a viral infection is misleading. However, cold weather may indirectly increase the likelihood of catching a “cold” due to increased sinus activity in inclement weather, but the virus must be present first.

 The Cold Weakens our Defenses

The cold weather can actually play a significant role in how our bodies react when they come in contact with a virus. When our bodies get cold their ability to fight off a virus is drastically decreased. According to one study by Shepard et al (1998), inclement weather plays a key role in the “suppression of several cellular and humoral components of the immune response, including a decrease of lymphocyte proliferation.” These lymphocytes are a type of white blood cell that play an important part in our immune system. They are responsible for identifying foreign invaders (like viruses) and using the body's immune system in an attempt to destroy them. Shepard goes on to say that,”Lymphocytes are an important unit in the immune response cascade that if not present result in a decrease in natural killer cell count. These Natural Killer cells are a specific type of lymphocyte that act as one of our first lines of defense. They provide rapid identification and destruction of infected viral cells without prior exposure needed. Without natural killer cells it would be much harder for our bodies to react to pathogens because our bodies' other immune responses such as T and B cells, take longer to respond.

             Another thing to keep in mind is that certain demographics will be affected more by the cold than others. For example, children have a harder time regulating their body temperature and thus are much more likely to be affected. They are also more likely to have compromised or weakened immune systems that make viral exposure more serious. Children, unlike most adults, don't have fully developed immune systems yet and lack vital components of the adaptive immunity such as “B” and “T” cell abundance. According to a study conducted by Semmes et al (2021), children under 6 only contain 60-75% of certain types of B cell activity (Figure 1). B cells are of vital importance as they produce antibodies that are  used to fight off viral pathogens.

Figure 1.  B and T cell availability in children under 6 and adults of 18 years of age.  This data was gathered research conducted by Semmes et al., 2021.

Cold to Action

The most important thing when the weather gets cold, regardless of if you're putting a jacket on or not, is to keep yourself out of harm's way during this year's cold and flu season. Make sure to wash your hands frequently to keep viruses and other unwanted bacteria away. It's also a good idea to stay home if you think you're getting sick. This will prevent the spread to those more susceptible demographics that may have a harder time fighting off illness.

 

Staying Warm in the Cold

Some may think that it's the cold weather that gives you a virus due to the cold-like symptoms that commonly arise during the winter months, such as a runny nose and sore throat. These symptoms are often mistaken for a cold/virus, but in reality they are just a result of your body reacting to the dry/cold air. The increased exposure to viruses from coughing and sneezing of infected individuals, along with your weakened immune system from the cold is the real culprit. Putting on your coat won't necessarily prevent you from catching a cold/virus. But it will help your body stay warm and reduce the conditions that make you more susceptible to illness.So next time you run outside give your body a fighting chance by taking a coat with you.

By Adam Singer, a Master's of Medical Science student at the University of Kentucky

References

 

Centers for Disease Control and Prevention. (2024, April 24). About Rhinoviruses. Centers for Disease Control and Prevention. https://www.cdc.gov/rhinoviruses/about/

Centers for Disease Control and Prevention. (2024b, October 15). About common cold. Centers for Disease Control and Prevention.

https://www.cdc.gov/common-cold/about/index.html#cdc_disease_basics_causes_risk_s pread-causes-and-spread

Shephard RJ, Shek PN. Cold exposure and immune function. Can J Physiol Pharmacol. 1998 Sep;76(9):828-36. doi: 10.1139/cjpp-76-9-828. PMID: 10066131

 

Semmes EC, Chen JL, Goswami R, Burt TD, Permar SR, Fouda GG. Understanding Early-Life Adaptive Immunity to Guide Interventions for Pediatric Health. Front Immunol. 2021 Jan 21;11:595297. doi: 10.3389/fimmu.2020.595297. PMID: 33552052; PMCID: PMC7858666.