A Answers (1)
Discovery Health answeredThere's more to developing allergies than just heredity. The things that you become allergic to are also based on when you're exposed to a substance and how much of it you're exposed to. Let's say, for example, that you have a tendency to be allergic to mold spores. You may have no allergy symptoms when you are living all alone in your spic 'n' span apartment complex. Then a new roommate moves in, bringing along a veritable jungle of houseplants, an smelly old mattress, and a humidifier (to keep her skin moist). Soon after her arrival, you become a symphony of snorts and sneezes. What happened? You'd endured a certain small amount of exposure to mold spores with no problem, but once the scales were tipped by the hefty onslaught of your roommate's mold-bearing possessions, your immune system kicked itself into high gear.