Hopkins research shows food allergies on the rise

An investigation on the national prevalence of food allergies led by Robert Wood, chief of Pediatric Allergy and Immunology at Hopkins, and colleagues indicates that black children with asthma are at highest risk for developing food allergies.

A food allergy is a hyperactive immune response to innocuous proteins present in certain foods. The body mistakenly considers the proteins that aren’t broken down in the digestive tract as harmful and tags them with immunoglobulin E (IgE), thus triggering a series of adverse reactions.

Allergic reactions range from mild to severe. Common signs include skin rashes and hives, swelling, nausea, vomiting and anaphylaxis.

“While we know food allergy is very common, there are very limited data as to just how common. This study was done to try to more accurately assess the prevalence of food allergy across the U.S.,” wrote Wood in an email to The News-Letter.

Based on interviews and blood samples of 8203 participants between ages one to greater than 60, researches estimated that approximately 2.5 percent of Americans have at least one type of food allergy.

“The most significant aspect [of this study] is the proof that food allergy is extremely common. These numbers are very important as we lobby for more funding for food allergy research,” wrote Wood.

In this study, four prevalent allergies were tested: peanut, shrimp, egg and milk. Results showed peanuts to be the most common allergen (1.5 percent), followed by shrimp (1 percent), eggs (0.4 percent) and milk (0.2 percent).

Furthermore, statistical analysis shows that black people are three times as likely as white people to have food allergies, men were about 1.9 times more likely than women, and children under five years of age more than twice as likely than those over 20.

Findings also show that those with asthma are four times more likely than those without to have a food allergy. Asthmatic individuals with food allergies were seven times more likely to require ER treatment for asthma. The cause of this relationship is currently unknown.

Correlations between hay fever and food allergy, and between eczema and food allergy were insignificant.

“As far as prevalence studies, we hope to be able to repeat this over the next 5-10 years. This will be important since we believe that food allergy is rapidly increasing but do not have food statistics to know just how much and how fast this is occurring,” Wood wrote. “We are also doing man other food allergy studies that focus on who gets it and why they get it, the natural history of food allergy and potential treatments for food allergy.”