What’s behind the startling explosion in nut allergies among children?

What’s behind the startling explosion in nut allergies among children? Is it changes in the kids, the peanuts or the processing?

—Lynne Whetzel, Ithaca, NY

Recent research does in fact show that the incidence of nut allergies among American and British children has tripled within the last two decades. No one knows for sure why, but because the phenomenon seems to be occurring only in developed countries, some environmentalists believe that pollution and synthetic chemicals might be to blame. An allergic reaction happens when the body’s immune system overreacts to a perceived threat, and researchers believe there may be an as-yet undiscovered link between exposure to various chemicals, pollutants and food additives and an overall rise in immune system disorders.

Parents of children suffering from nut allergies live life constantly checking the ingredients on food labels. Nuts and nut oils are used in an increasingly wide range of processed foods, including many of the chips and cereals preferred by kids today. The ubiquity of snack foods throughout our society makes it difficult for kids to avoid nuts and nut oils, even if they know they are allergic.

Nut allergies can start early on and usually do not go away in adulthood. From the second trimester of pregnancy on, the unborn fetus can recognize allergens to which the mother has been exposed, and may at this early point begin to develop sensitivities that can lead to allergic reactions following birth. Pregnant women with a history of allergic reactions can minimize the risk to their children by avoiding certain known allergens, especially tree nuts (cashews, almonds, pecans and walnuts) and peanuts. Breast-feeding mothers should also avoid foods that contain these allergens, as they can be transmitted to babies via breast milk. Additionally, several leading brands of creams used by mothers to ease discomfort while breast-feeding contain nut oils which can trigger allergic reactions in babies as well.

Symptoms of nut allergies, as with many allergies, can range from mild reactions like watery eyes, an itchy throat or a runny nose, to severe reactions like eczema, hives, nausea and vomiting. In extreme cases, allergic reactions can lead to anaphylaxis, a life-threatening condition hastened by the body’s release of toxic amounts of histamine into the blood stream.

The Fairfax, Virginia-based Food Allergy & Anaphylaxis Network is a non-profit organization that raises awareness about and conducts research on food allergies and anaphylaxis. The organization’s diverse membership makes it the leading clearinghouse on food allergies in the U.S. Meanwhile, the Farnborough, England-based Anaphylaxis Campaign provides similar services in the U.K. and beyond. These groups can be invaluable to families struggling through food allergies.

CONTACTS: Food Allergy & Anaphylaxis Network, (800) 929-4040, www.foodallergy.org; Anaphylaxis Campaign, www.anaphylaxis.org.uk.