Why do we get allergies?


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An allergic reaction occurs when the body’s immune system identifies an allergen (usually a protein) as a dangerous threat. It releases IgE (an antibody) into the circulatory system to set off a chain reaction of chemical releases from other cells in order to destroy what it sees as the threat. This release of biological chemicals (including histamines) is what causes the symptoms of an allergic attack.

There are many different factors that play a role in our body’s development of allergies. Unfortunately, our family history plays a big part in the way our immune system views the things that get into our body. Genetic predisposition means that you are more likely to suffer from allergies than someone who is not predisposed. Scientists have discovered that genes found on chromosomes 5 and 11 are responsible for our predisposition to an allergy prone immune system. If allergies run in your family, chances are, you will suffer from them at some point in your life.  Evidence also suggests that males are more likely to suffer allergies, as are families with fewer children. Obesity can also put you at an increased risk of developing allergies, as can the diet your mother was on before you were born.

The environment in which we spend the first year of our life can influence our chances of developing allergies. Second hand smoke has been linked with allergies, in addition to antibiotics and the type of diet you are exposed to. Even the day you are born can be a factor. For example, if you are a spring baby, the exposure to the pollens in the air at that time of the year can cause a sensitisation reaction in your immune system and leave you with a high likely hood of developing hay fever.

Finally, your immune system won’t become sensitive to any particular allergen without the actual exposure to it. You cannot become allergic to peanuts if you have never actually eaten them at least once.

Read more in the Allergies Information Guide »