Food allergies a growing concern

WASHINGTON, Jul 08, 2005 (United Press International via COMTEX) -- Biological weapons may be a distant concern for most Americans, but some struggle to avoid them every day -- in the form of canned tuna laced with milk protein, fruit popsicles manufactured with dairy-contaminated equipment or enchilada sauce containing hidden peanut protein.

According to the American Academy of Allergy, Asthma and Immunology, up to 8 percent of children and 2 percent of adults in the United States suffer from food allergies.

For people with severe allergies, consumption of minute amounts of an ordinary food such as milk, peanuts or shellfish commands the immune system to unleash a full-scale assault on the rest of the body. This can lead to consequences such as skin eruptions, asthma attacks, gastrointestinal problems and potentially fatal systemic allergic reactions called anaphylaxis.

Anne Munoz-Furlong, founder and chief executive officer of the Food Allergy and Anaphylaxis Network in Fairfax, Va., said at a recent briefing for reporters that dealing with food allergies can impact areas of life as far-reaching as grocery shopping, schools, child care, dining out, socializing, traveling and even family relationships.

The only current method for averting food-related anaphylactic reactions is avoiding the foods responsible -- a process that entails careful reading of food labels and being wary of possibilities for food cross-contamination.

Even label reading is not as simple as it sounds, according to an AAAAI pamphlet, because many common allergens are listed on labels under uncommon aliases. For instance, milk can masquerade as casein, caseinates, rennet casein, lactalbumin, lactalbumin phosphate, lactoglobulin or lactulose.

"Shopping went from about a half-hour process to a three-hour process," Hugh Sampson, director of the Jaffe Food Allergy Institute at the Mount Sinai School of Medicine in New York City, said at the briefing. He was describing his experience after his child was diagnosed with an egg allergy.

Munoz-Furlong said a food-labeling law is scheduled to take effect in January to make the identification of allergen-containing foods easier, although it will take another year for the changes to be fully implemented.

Many children outgrow their food sensitivities, but a recent rise in the incidence of peanut allergies shows the problem of food-related anaphylaxis will become increasingly prevalent in the United States. Sampson said he conducted procedurally identical studies in 1997 and 2002 to determine U.S. rates of peanut allergies. He found the rate in children younger than age 5 doubled during that time.

About 80 percent of allergic reactions in children are due to milk, eggs and peanuts, and though they will often outgrow allergies to milk and eggs, only 21 percent do so, the AAAAI pamphlet said.

The reason for the increase in peanut-allergy rates is unknown. Sampson said the Chinese eat as many peanuts per capita as Americans do but have virtually no problems with allergies, while the United States has the highest peanut-allergy rate in the world. He suggested the U.S. method of processing peanuts by dry roasting, rather than boiling and drying, could play a role.

There are various theories regarding the rise in allergy rates. The "hygiene hypothesis," for example, holds that the sanitary conditions of modern life contribute to increased allergy rates because immune systems are inadequately stimulated. Another possibility is the environment is becoming more allergenic. For instance, pollens in polluted cities seem more potent than varieties in rural areas, Sampson said.

He also noted that some people are only allergic to shrimp when they consume alcohol at the same time, because alcohol increases the absorption of proteins. Likewise, some people react allergically to foods only if they exercise within two or three hours of eating the food, for reasons unknown -- and some people can eat a food without incident for years and suddenly develop an allergy.

"You get the right combination at some point and then you become allergic," Sampson said.

Carlos Camargo Jr., an associate professor of medicine and epidemiology at Harvard Medical School, said at the briefing there have been difficulties obtaining food-allergy research funding from the Food and Drug Administration and the National Institutes of Health. He said researchers want to study genetic traits, but the NIH wants them to gain a better understanding of what they are seeking before granting funding.

Camargo described the FDA as "struggling to do its job" under pressure from companies that do not want potentially negative research conducted about their products.

"It really has to come from the federal and state government, and donations to organizations like FAAN," he said.

Munoz-Furlong said the government allocates only $5 million to $7 million per year for food-allergy research, compared with $1 billion for diabetes research. According to the American Diabetes Association Web site, 6.3 percent of the U.S. population has diabetes.

Along with the funding issue, another obstacle to food-allergy research is the lack of a universal definition for anaphylaxis.

"It's very hard to study something if you can't define it in a consistent way," Camargo said.

In a recent study, Camargo defined the condition was either the involvement of two or more organ systems (skin, respiratory, cardiovascular, gastrointestinal) or hypotension, which is systolic blood pressure below 100 millimeters of mercury. Anaphylaxis can occur in response to insect stings and medications, as well as food allergies.

The confusion over defining the disease often results in inadequate medical treatment, he said.

Through reviewing patient charts at an assortment of major American hospitals, Camargo found, on average, only 16 percent of people who visited emergency rooms for food-related anaphylaxis were prescribed EpiPens, which contain injectable epinephrine that can be used to buy time while awaiting medical treatment in event of a future anaphylactic reaction.

Only 12 percent of ER patients exhibiting anaphylaxis were told to visit an allergist.

Many patients were not even advised to avoid the specific food that had caused their reaction. This might sound obvious, Munoz-Furlong said, but many people who have died from anaphylactic reactions had visited emergency rooms many times previously for the same condition without ever being told their allergies could kill them.

Jonathan Bernstein, associate professor of medicine at the University of Cincinnati Medical Center, told briefing attendees that possible avenues for research include studying when and how to introduce potentially allergenic foods to babies and what at-risk mothers should eat during pregnancy and breastfeeding.

"I think from the patient perspective, until we find a cure and we increase the funding for research, we've got to keep these people safe," Munoz-Furlong said. "So, funding for education so that teachers can be prepared, physicians can make the right diagnosis, emergency room staff know what to do and what to tell the patient when they leave -- it's got to be a two-pronged approach, with the research to find the cure but also the education and awareness to keep these people safe."

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Eva A. Sylwester is an intern for UPI Science News. E-mail: sciencemail@upi.com