An Allergy as we all know is a serious threat to the human body. There are various myths about allergy but the fact is that it affects the immune system very gravely and makes life difficult for a human being.

However, there are basically two causes of allergies that mainly result in allergic reactions:

1. Genetic (or hereditary) factors

Some diseases have their origin based on their parents. It has been found that there are chances that the newly born child may have the diseases that were there in his/her fathers and fore fathers. However, allergy is not always inherited; chances are not 100% as genetic factor always does not play the deciding part in weakening the immune system.

2. Environmental factors

On the other hand, environmental factors can cause allergic reactions as the world around us is getting full of environmental pollution and that too at a rapid pace, which affects the immunity of our body. Any of the foreign substances that we touch, swallow or breathe are responsible for allergic responses from our immune system. These are known as Allergens and some of the common allergens include pollen, mold, pet dander, and dust. Food allergy and drug allergy are common.

Allergic reactions can also be caused by insect bites, jewelry, cosmetics, and other substances and can take us towards many other diseases. So basically allergens are responsible for weakening the immunity of the body.