Contrary to the many lists declaring the top worst cities for allergy suffers, new research shows the prevalence of allergies is the same regardless of where you live, with the exception of allergies among children 5 years old and younger.
In the study, researchers analyzed blood serum data compiled from roughly 10,000 adults and children in the National Health and Nutrition Examination Survey (NHANES) 2005-2006. Their findings constitute the largest and most comprehensive nationwide study to examine allergy prevalence from early childhood to old age.
Results showed that only children ages 1-5 from the southern United States displayed a higher prevalence of allergies than their peers living in other regions. Paivi Salo, PhD, lead author and an epidemiologist National Institute of Environmental Health Sciences, explained in a release, "The higher allergy prevalence among the youngest children in southern states seemed to be attributable to dust mites and cockroaches... As children get older, both indoor and outdoor allergies become more common, and the difference in the overall prevalence of allergies fades away."
Other interesting findings from the study include:
The study found that in the 6 years and older group, males, non-Hispanic blacks, and those who avoided pets had an increased chance of having allergen-specific IgE antibodies, the common hallmark of allergies.
Socioeconomic status (SES) did not predict allergies, but people in higher SES groups were more commonly allergic to dogs and cats, whereas those in lower SES groups were more commonly allergic to shrimp and cockroaches.
By generating a more complete picture of U.S. allergen sensitivity, the team uncovered regional differences in the prevalence of specific types of allergies. Sensitization to indoor allergens was more prevalent in the South, while sensitivity to outdoor allergens was more common in the West. Food allergies among those 6 years and older were also highest in the South.