In the first study of its kind, scientists geographically mapped children's food allergies across the nation. The results show that children in urban environments have a higher prevelance of food allergies than their rurual counterparts. Specifically, children living in major metropolitan areas were more than twice as likely as those in rural areas to have shellfish and peanut allergies.
"This shows that environment has an impact on developing food allergies,"said the study's lead author Ruchi Gupta, M.D. Gupta is a physician at the Ann & Robert H. Lurie Children's Hospital of Chicago and an assistant professor of pediatrics at Northwestern University Feinberg School of Medicine. "Similar trends have been seen for related conditions like asthma. The big question is – what in the environment is triggering them? A better understanding of environmental factors will help us with prevention efforts," she said.
The study, which will be published in the July issue of Clinical Pediactrics, included nearly 38,500 children who were 18 years old and younger, and their food allergies were mapped by ZIP code. Food allergies were tracked in environments classified as urban centers, metropolitan cities, urban outskirts, suburban areas, small towns, and rural areas. Other aspects of the children's lives like household income, race, and gender were controlled so as not to impact the data with too many variables.
According to the study, Nevada, Florida, Georgia, Alaska, New Jersey, Delaware, Maryland and the District of Columbia had the highest overall prevalence of food allergies. Moreover, data showed that food allergies are equally severe regardless of where a child lives, and almost 40 percent of children in the study had already experienced a severe, life-threatening allergic reaction to food. Last year, Gupta conducted research that showed that approximately one out of every 13 children has a food allergy that is potentially life-threatening. Put another way, 5.9 million people under 18 years old are affected wtih a food allergy.
Although there is no definitive answer currently as to why urban environments foster more food allergies, scientists have some theories. An article on Eurekalert explains, "One hypothesis is that exposure early in life to certain bacteria associated with rural living may protect against hereditary hypersensitivity to certain allergens. Or, many pollutants encountered in urban areas may trigger the development of these allergies."
Eczema and conjunctivitis, commonly called Pink Eye, are also more prevelant in urban environments than rural ones.
