Do you suffer from allergies? Do any of your children have the same allergies that you do? Most people realize that allergies tend to run in families. There are many theories as to what causes an person to become allergic to something, and studies are still being done in order to find that out. A recent study concludes that first born children are more likely to suffer from allergies than their younger siblings are.
The National Institute of Allergies and Infectious Diseases says that about 26 million Americans suffer from seasonal allergies. WebMd says that one in five people suffer from allergies of some kind.
An allergy can be defined as an abnormal response of the immune system, when it encounters a substance in the environment that is usually harmless to other people. That substance is called an allergen. This means that people who have an allergy to something are going to have a physical reaction after coming in contact with a substance that most other people don’t have any need to be consciously aware of. Some people, both children and adults, have allergies that are so severe that they could, in fact, die from exposure to that particular allergen.
There are a lot of theories about what, exactly, causes a child to develop allergies. Some say that being exposed to certain foods, like peanuts, or eggs, at a young age can “cause” an infant to become allergic to that food. It’s been said that nasal allergies can develop in children who live with a person who smokes. Some feel that babies who were bottle fed, instead of breast fed, are at a risk for developing allergies. Most people who have allergies know of at least a few relatives who also have allergies, which indicates allergies can run in families.
Researchers in Japan have found that first born children are more likely to suffer from allergies than their younger brothers and sisters are. They surveyed the parents of 13,000 school aged children, and asked the parents the order of their children, and what allergies the children had. The children ranged in age from seven to fifteen years old. They found that 4% of first born children had rhinitis, conjunctivitis, and food allergies. Only 3.5% of second born children had these allergies, and just 2.6% of third born children suffered from allergies.
Researchers felt that there should be more studies that focus on the pre-natal and post-natal circumstances on a child in order to gain a better understanding of what, exactly, caused the first borns to be more allergic than the other children in their families.
One theory that may explain why first borns were more prone to allergies was called the “hygiene hypothesis”. First time parents tend to be really nervous about everything that has to do with their brand new baby. They tend to over sterilize their homes. This means that first born children aren’t exposed to as many germs as their younger brothers and sisters will be. When the body is exposed to certain kinds of household germs, it helps the body to build up it’s immune system. As a family has more children, they become less nervous, and usually stop over-sterilizing their homes.
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