About 4 Percent of Americans Suffer From Food Allergies

Millions of Americans have had to swear crustaceans, eggs, peanuts or soya to avoid allergic reactions that can range from stomach cramps to deadly swelling of the airways, according to new research.

About 4 percent of Americans have a food allergy, with women and Asians most affected, according to the study.

"Recent reports suggest that food allergies are on the rise, with more hospitalizations related to food allergies in the United States over the past decade," said lead researcher Mr. Li Zhou. She works with the Division of General Practice and Primary Care at Brigham and Women's Hospital in Boston.

Food allergies cost the United States about $ 25 billion annually, Zhou said.

For the study, Zhou and colleagues examined nearly 3 million medical records identifying over 97,000 patients who had one or more food allergies or an intolerance to a food.

The most common allergy has been for crustaceans, such as shrimp and lobster, said Zhou.

"In addition, 1 in 6 patients with food allergy or intolerance had documented anaphylaxis [fatal swelling of the respiratory tract]," she noted.

Other common food allergies included fruits or vegetables, dairy products and peanuts, the researchers found.

Food allergies can lead to reactions such as hives, anaphylaxis, shortness of breath, wheezing, itching, swelling or allergic reactions called intolerances, Zhou said.

His team found nearly 13,000 patients were allergic or had peanut intolerance, including more than 7,000 hives, anaphylaxis or other reactions.

But, only 1 in 5 patients with peanut allergy received allergy follow-up tests, said Zhou.

Given the number of people in the US with food allergies, researchers believe that other allergists are needed.

"The spectrum of severity observed with food allergy underscores the critical need for more allergic assessments," said Zhou.

The report was published on 31 May in the Journal of Allergy and Clinical Immunology.

In addition to crustaceans, peanut, walnut, egg and milk allergies are common, said Dr. Alisa Muniz Crim, a gastroenterologist at Nicklaus Children's Hospital in Miami.

Patients who have an anaphylactic reaction to a food should exclude these foods from their diet, said Crim, who did not participate in the study.

"Many of these patients have to carry an EpiPen, which contains the epinephrine drug that acts quickly to open the airways, leaving the patient breathing," she said.

Among children, common reactions are stomach cramps, vomiting, rashes and diarrhea, said Crim.

Some food allergies can be treated by gradually exposing patients to increasing amounts of allergic food until they take a tolerance there, said Crim. But for people with severe allergies, avoidance is the best treatment, as well as anti-allergic drugs, she said.

Crim believes that schools should have kits that include an EpiPen to treat children who have an allergic reaction.

Dr. James Baker Jr., CEO and Chief Medical Officer of Health of Food Alergie Research and Education, said it was a matter of 1 of 6 patients with a food allergy in this study had anaphylaxis.

"Avoiding or preventing these serious reactions is crucial to ensuring the safety of people suffering from food allergies," he said.