Humidity of 50 percent or more triggers asthma Two common theories for this are: Humid air is heavier and harder to breath and humid air harbors fungus, mold and dust mites that trigger asthma. Air that is too dry can trigger asthma When you inhale cold air that is dry this can dry the mucus membranes lining your lungs that are your bodies natural defense mechanisms against viruses and bacteria. So this can lead to increased infections too. And viral infections are the most common... Read More