Seasonal allergies occur when your innate immune system perceives airborne pollen as a threat and overreacts to its presence in your body with a flood of histamine, producing runny nose, itchy eyes, nasal congestion, sneezing, headaches, and other symptoms. This type of response makes sense with foreign substances that are intrinsically dangerous, like pathogenic microbes, poisons, and toxins, but there’s nothing inherently dangerous about pollen. What gives?

(This Mark's Daily Apple article was written by Mark Sisson, and is narrated by Tina Leaman)