Scientists from Ann & Robert H. Lurie Children's Hospital of Chicago and Northwestern University looked at data from a survey of 40,000 adults. Out of those surveyed, 10.8% reported severe allergy symptoms like a tightening throat and anaphylactic shock, and another 8.2% said they believed they had allergies, without those symptoms.
"While we found that one in 10 adults have [a] food allergy, nearly twice as many adults think that they are allergic to foods, while their symptoms may suggest food intolerance or other food related conditions," said Ruchi Gupta, a doctor from Lurie Children's and lead author of the study.
"It is important to see a physician for appropriate testing and diagnosis before completely eliminating foods from the diet. If food allergy is confirmed, understanding the management is also critical, including recognizing symptoms of anaphylaxis and how and when to use epinephrine."
Just half of those with a severe allergy had a physician-confirmed diagnosis, the results suggested, and less than a quarter said they had a prescription of epinephrine or an "EpiPen" that usually relieves the symptoms of an allergic reaction.
The most common food allergies among US adults are shellfish (affecting 7.2 million adults), milk (4.7 million), peanuts (4.5 million), tree nuts (3 million), fish (2.2 million), eggs (2 million), wheat (2 million), soy (1.5 million), and sesame (0.5 million).
The team were surprised to find that nearly half of allergic respondents developed at least one of their food allergies as an adult.
"More research is needed to understand why this is occurring and how we might prevent it," said Gupta.
Gideon Lack, a professor of paediatric allergy at King's College London, told The Guardian there has been a rise in children developing food allergies in recent years.
"We have been focusing efforts and concerns about food allergy in children," he said. "And this study is telling us there is a very significant burden of food-allergic disease in adults and we ought to be directing more attention and resources towards diagnosing and treating those adults."
