Keeping cool can make you sick.
If you’ve ever felt a sniffle coming on in the summer months — particularly when you’re on vacation — then air conditioning could be to blame.
But what is it, and is it a real illness?
According to a 2004 study in the Journal of Epidemiology, there is some science to support “air con sickness.” Researchers found that being in air conditioning — if the unit has not been maintained or is in a poorly ventilated building — can cause health problems.
Working or living in a poorly ventilated building with air conditioning can raise your risk of “sick building syndrome,” a term used to describe collective symptoms experienced by a building’s occupants, according to the EPA.
Symptoms may include headaches, dry cough, dizziness, nausea, trouble concentrating, fatigue and odor sensitivity.
Science ABC reported that when air conditioners are not properly maintained or cleaned, they are potentially filled with bacteria and mold. This can mean that the unit may circulate infected air.
Heating, ventilation and air conditioning units are designed to filter air pollutants and contaminants from indoor air, however, if the filters are not cleaned properly they become prime space for air particles and microorganisms to breed. This may trigger asthma, allergies and other respiratory symptoms.
“Dirty air conditioning filters may be contaminated with mold, fungus or other microorganisms,” a representative for the California Department of Public Health told Verywell. “This may lead some occupants, especially if sensitive to molds, to have breathing problems.”
Last year, Dr. Nathan Spence posted a video to TikTok about why the phenomenon occurs.
In the video, he explained there is a type of pneumonia that can be caused by air conditioning. Dirty air conditioning units in hotel rooms can trigger a condition known as Legionnaires’ disease, which causes “an atypical chest infection that requires antibiotics.”
The disease is a serious type of pneumonia caused by the Legionella bacteria, which can be contracted by inhaling droplets of water from things like air conditioning or hot tubs, according to the CDC.