A study published in the October issue of the Journal of Allergy and Clinical Immunology estimated that nearly 2.5 percent of Americans have at least one food allergy. The study, which is believed to be the largest food allergy study to date, showed that the allergies were more common in children 5 years old or younger.
In the study, children under the age of 5 were more than twice as likely as those older than 20 to have a food allergy and black people were three times as likely as white people to have one, while men were nearly 1.9 times more likely than women to be affected. Black boys were more than four times as likely as white women over 20 to have a food allergy.
The findings also show that food allergies were more common in those with asthma. While the researchers did not study cause and effect between food allergies and asthma, having a food allergy appeared to compound the risk for asthma and vice versa.
Those with asthma had nearly four times the risk of having a food allergy than those without it. Overall, people with food allergies were nearly seven times more likely than those without them to have required ER treatment for their asthma in the 12 months leading up to the study.
“Our findings confirm a long-suspected interplay between food allergies and asthma, and that people with one of the conditions are at higher risk for the other,” says investigator Robert Wood, M.D., director of Allergy and Immunology at Hopkins Children’s.
Wood notes that many children experience an “allergic march,” developing a food allergy first and getting asthma and hay fever later.
While people with food allergies were somewhat more likely to be diagnosed with hay fever, the link between the two was not particularly strong, and they did not appear to have higher risk for eczema, the investigators found.
