By Sally Squires
Tuesday, July 10, 2007
For the estimated 12 million Americans with food allergies, eating can be quite an adventure.
Just ask Chris Paganelli, 54, who has been allergic to eggs and chicken since childhood.
"I always joke that I am not very much fun to go out to a new restaurant with, because I end up being pretty neurotic," says the pharmaceutical rep and father of two, who lives in Silver Spring.
Can you blame him? At a recent business conference in Chicago, Paganelli made sure to let organizers know in advance of his allergy to chicken and eggs. So he thought it was safe to eat what appeared to be mozzarella on his luncheon salad. About 10 minutes later, Paganelli doubled over and got violently ill. He had accidentally consumed a large helping of chopped boiled egg whites -- one of the foods to which he is most allergic.
Like many people with food allergies, Paganelli has learned the hard way to be prepared. He reached for his emergency medical kit and quickly jabbed himself with an auto-injector of epinephrine to ward off anaphylactic shock, an allergic reaction that can be fatal in minutes. Even though he and many others need to take such extreme measures to protect themselves, Paganelli says most people still don't think that food allergies are "that big a deal."
Yet, some 30,000 people are sent to emergency rooms in the United States each year for food allergy attacks, which claim 100 to 200 lives annually. If it seems as if food allergies are on the rise, it's not your imagination.
"For reasons that we don't understand, the prevalence of food allergies has doubled in the last 15 years," notes Wesley Burks, chief of allergy and immunology at Duke University Medical Center. In a recently released report, the National Institute of Allergy and Infectious Diseases (NIAID) calls food allergies an emerging and "important public health problem."
Among the theories for the increase are changes in the way food is processed and the age when solid food is introduced to infants. Some experts also contend that our obsession with cleanliness overprotects the immune system, which then reacts too aggressively when confronted with perceived foreign invaders, such as peanuts, instead of just taking them in stride.
During a food allergy attack, the immune system overreacts to specific food proteins and manufactures too much immunoglobulin E (IgE). That in turn sets in motion a series of reactions that can produce anything from itchy hives and a runny nose to a life-threatening anaphylactic attack. (See the accompanying box for more on symptoms.)
How severe the reaction is varies according to how many times the offending food has been eaten, how much is consumed and the genetic makeup of the allergic person. Some of the most severe attacks occur from eating peanuts and tree nuts such as cashews.
Food allergies now afflict about 4 percent of adults and 8 percent of children aged 2 and younger, according to Marshall Plaut, chief of the NIAID's Allergic Mechanisms Section.
The good news: Studies show that many children outgrow their allergies. That's already happened for Gavin Perkins of West Hartford, Conn. Just 14 months old, he seems to have outgrown an allergy to wheat, although he still is allergic to chicken, eggs, dairy, soy and fish. Since Gavin breast-feeds, that means his mother, Lisa, has to be very careful about what she eats, too, because food proteins pass through breast milk.
"I can't rely on a lot of processed foods, because soy and dairy are in almost everything," says Perkins, who has been diagnosed herself with an allergy to fresh apples -- although cooked are okay -- and to cantaloupe.
Doctors diagnose food allergies through blood and skin tests coupled with a physical exam and a history of food-related problems. Studies suggest that about 30 percent of people who think they are allergic, prove not to be.
Any food can produce an allergic attack, notes allergist Paul J. Hannaway, author of "On the Nature of Food Allergy."
But Robert A. Wood, a doctor at Johns Hopkins University, wrote in a report in the journal Pediatrics in 2003 that just eight foods -- milk, eggs, peanuts, tree nuts, fish, shellfish, soy and wheat -- account for about 90 percent of the food allergy reactions in the United States. Allergy to milk proteins is the most common in the United States. (This allergy is different from lactose intolerance, a condition that causes intestinal distress and other problems and afflicts 30 million to 50 million Americans who don't have an enzyme needed to digest the sugar, lactose, found in dairy products.)
The only sure way to manage food allergies is to avoid foods that cause the reactions and to be prepared for the problems that can be caused by accidental exposure.
Sometimes even the experts can be fooled.
Wood, who has a peanut allergy, was once given homemade cookies by a grateful patient's parent. He was assured that the cookies did not contain peanuts. But they had been baked on a cookie sheet that had previously baked cookies with peanuts. The residue was enough to send Wood into an anaphylactic attack that required three shots of epinephrine to reverse.
Since January 2006, the Food and Drug Administration has required food manufacturers not only to list leading food ingredients that could cause allergies, but also to indicate if products had been produced on equipment that could contain residues of allergy-causing foods such as peanuts or soy.
But a study published last week suggests that the warnings are now given so frequently that "consumers assume they are not serious," notes the study's co-author, Scott Sicherer of the Jaffe Food Allergy Institute at Mount Sinai School of Medicine in New York.
The study also found that the warnings "do not reflect the degree of danger" for those with food allergies.
That's why longtime food allergy sufferers often yearn for something that will eliminate their condition. "I wish there was something new for treatment," Paganelli says.
There may be. Burks and his colleagues at Duke are one of several groups exploring ways to help tame overreactive immune systems. Results have been promising enough that Burks predicts some treatment could be available in the next five years.
In the meantime, here's what experts recommend for people with food allergies:
· Always read food labels. Formulations of products can change without notice.
"Don't assume that because it was safe last month, that it will be safe this month," says Anne Muñoz-Furlong, founder and head of the Food Allergy and Anaphylaxis Network.
· Look beyond traditional food products.
Pet food and bath products can often contain food allergens. These and other products can be especially dangerous for toddlers and young children who might pick up food left out for a pet or react to bath products.
· When in doubt, ask. Not sure about a product's ingredients? Call the manufacturer.
"Don't just ask what it contains," Muñoz-Furlong says. "Ask specifically if it contains the ingredient or ingredients that cause your allergy."