Allergy Basics
Allergies are the result of a hyper-active immune system. People
who have allergies have an overly alert immune system that reacts
to a substance in the environment called an allergen. For most people,
exposure to a substance such as pollen is harmless; to a person
with allergies the exposure can cause mild to severe reactions.
Allergies are a common health problem, affecting at least 2 out
of every 10 Americans. Most allergies are inherited, passed on to
children by their parents. People inherit a tendency to be allergic,
although not to any specific allergen. When one parent is allergic,
their child has a 50% chance of having allergies. That risk jumps
to 75% if both parents have allergies.
Allergies are the result of a hyper-active immune system. People
who have allergies have an overly alert immune system that reacts
to a substance in the environment called an allergen. For most people,
exposure to a substance such as pollen is harmless; to a person
with allergies the exposure can cause mild to severe reactions.