Peanut Allergy: What can be done

Healthfacts, May, 2002 by Maryann Napoli

An estimated 3 million Americans are allergic to peanuts and/or nuts that grow on trees, such as walnuts, cashews, and pistachios. The allergy accounts for the majority of fatal and near-fatal anaphylactic reactions. In a recent review of this topic for The New England Journal of Medicine, 4/25/02), Hugh A. Sampson, MD, wrote that 80% of the people who died from allergic reactions to food had not been given appropriate information about how to: avoid accidental food-induced reactions, recognize early symptoms, and self-treat immediately.

The rising incidence of peanut allergy in the U.S. and other westernized countries cannot be explained by the ever-increasing consumption. The per capita consumption of peanuts in the U.S. is similar to that of China where peanut allergy is rare. One possibility described by Dr. Sampson is the differences in how peanuts are cooked. In the U.S., most peanuts are dry-roasted, including those destined for peanut butter. But in China, peanuts are typically boiled or fried.

The high temperatures required for dry roasting, he explained, increase the allergenicity of the three major peanut proteins more than do the lower temperatures used for boiling or frying. Additional support for the cooking theory comes from the observation that the children of Chinese immigrants to the U.S. show the same prevalence of peanut allergy as the children of native-born Americans.

Peanut allergy usually shows up first in early childhood, says Dr. Sampson, but unlike many other food allergies in children, this one is often a lifelong problem. He alerts fellow physicians in this article to the common occurrence of inadvertent exposure that occurs every three to five years in the average person with peanut allergy. Therefore, Dr. Sampson advises doctors to prepare their patients with a written emergency plan and the means to medicate themselves.

Since researchers suspect that the first exposure might occur in utero, during breast-feeding, or early childhood, prevention is the best course of action. For example, women from families with a history of peanut allergy should not eat peanuts during pregnancy and lactation. Nor should children from such families be given peanuts or any type of nut in the first three years of life. Also, children in whom an allergy to milk or eggs develops during the first year of life will have a 30% chance of developing a peanut allergy.

Resource Contact the Food Allergy and Anaphylaxis Network at 1(800) 929-4040 (www.foodallergy.org) where you will find information, ranging from hidden sources of peanuts to a written description emergency plan for self-injectable epinephrine. The FAAN claims a more than 24,000 members worldwide and includes families, dietitians, nurses, physicians, school staff, representatives from government agencies, and the food and pharmaceutical industries.

--- MaMaryann Napoli is the associate director of the Center for Medical Consumers in New York City.