The usage of cool mist and steam humidifiers are common when it comes to treating cough and cold symptoms. According to the CDC, cool mist humidifiers can soothe a cough by loosening mucus, but this is not a proven theory. It’s important to note that not all coughs are due to colds. While humidification might be inappropriate for a person with an asthma cough who is sensitive to humidity-loving allergen sources, they provide a comfortable and cozy environment at home, so cold and cough symptoms won’t get aggravated if you install them. Even if they don’t contribute to reducing these symptoms, the air quality in your home drastically improves for sure.