Allergy Basics: What Are Allergies?

Allergies are an unusual illness because they are not caused by bacteria, viruses, or other classic bugs you may be familiar with. On the contrary, allergies are caused by your own body reacting to something harmless as if it were an enemy. This being the case, allergy basics begin in your immune system. Normally, your immune system is responsible for protecting your body against foreign invaders that would cause your body harm, such as bacteria and viruses. If you have an allergy, your immune system will fight against innocuous substances in the environment, such as a ragweed allergy or pet dander.

While these allergy basics regarding your immune system may sound complex, allergies are a very common problem affecting about 50 million people in the United States. Delving further into allergy basics shows us exactly what is happening to cause allergy symptoms like sneezing and congestion. Here is a step-by-step process of basic allergy reactions:

(1) First, you are exposed to the allergen, also known as the “trigger” of your allergy symptoms.

(2) In response, your immune system makes antibodies called IgE to capture the allergen.

(3) The IgE antibodies seek out and attach to mast cells in your body. Mast cells, which are a type of blood cell, are located in your airways and in your digestive tract.

(4) Next, the allergens bind to the IgE antibodies which are attached to your mast cells. This causes your mast cells to explode and release many chemicals into your body. One of the main substances released is histamine. Histamine is mostly responsible for the basic allergy symptoms you experience.

Thankfully, not everyone has allergies, and it’s not fully understood why some people have allergic reactions while others don’t. By studying allergy basics throughout the entire population, it has been found that allergies seem to be inherited. If you have one parent with allergies, you have a 50 percent chance of having them, too. When both parents have allergies, your chance of having them increases to 75 percent.