Allergy is an instant hypersensitivity towards various matters. Opposite to food intolerance the reaction occurs instantly. it is due to an overreaction in your immune system. When your immune system creates antibodies towards an antigen, an antigen/antibody connection is created in your blood. This is normally harmless for the organism but not in all cases. Sometimes the immune system overreacts. This can for example be a reaction to grass pollen or a specific food. These reactions are normally harmless.
You become and allergic (hypersensitive) when your immune system triggers some immunological reactions that are damaging for the tissues or disrupts fysiological functions in your body. The antigen effects the specific immune system. That causes a production of antibodies and a chain reaction is initiated. When the immune system is overeacting, the reaction in your body is more powerful than necessary, which is an allergic reaction.
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