Wednesday, July 15, 2009
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Food Allergies: Q&A with Dr. Anne-Marie Irani
Food allergies affect
approximately 12 million Americans, around 6 to 8 percent of infants and young
children and 1 to 2 percent of adults.
Dr. Anne-Marie Irani has been practicing allergy
and immunology at the VCU Medical Center since 1986. She is the chair of the Division of Pediatric Allergy and
Immunology at the VCU Children's Medical Center and serves on the Board of
Directors of the American Academy of Allergy, Asthma and Immunology.
Q: Is it true that food
allergies always begin in childhood?
A: Most food allergies present in
childhood. Occasionally, new food allergies develop in adults when they are
exposed to a food they have not eaten in a long time. That's because regular
exposure (ingestion) of a food will maintain tolerance to that particular food.
Q: Do food allergies in
children go away as they get older?
A: Not all food allergies in children
resolve with age. The rate varies depending on the food. Eighty percent of
children with allergic reactions to cow's milk, egg or soy will lose these
allergies by age six, while only 20 percent of children allergic to peanuts
lose this allergy.
Q: Is any adverse
reaction to a particular food considered a food allergy?
A: Adverse reactions to a particular food are
often referred to as “food allergies.” However, this is incorrect. The term
“food allergy” should be reserved for reactions that are due to an immune
mechanism. Lactose intolerance, which is due to a deficiency of the enzyme
lactase, or food poisoning, which is due to a toxin in the food ingested, are
examples of adverse reactions to food that should not be referred to as “food
allergies.”
Q: What is the best way
to find out if you have a food allergy?
A: The best way to find out if you have a
food allergy is to seek the advice of a board-certified allergist/immunologist.
Consult the Academy’s website at aaaai.org to find a specialist near you.
Q: How do you diagnose
food allergies?
A: The diagnosis of food allergy requires a combination of a good history,
allergy skin testing, blood tests and, occasionally, a food challenge performed
in a medical setting. These tests do not give a “yes” or “no” answer and,
therefore, should be interpreted by specialists. For example, a person may have
a negative blood test to a particular food but still be allergic to that food.
Conversely, a low positive blood test or skin test may not indicate a true,
clinically significant food allergy.
For more
information, contact the Division of Pediatric Allergy and Immunology at 804-828-9620.