New research presented at the Ameican Colleege of Allergy, Asthma, and Immunology (ACAAI) has found that 45 percent of all American adults with food allergies have at least one allergy that didn't come until after adulthood. The research came after the research team found a growing prevalence of food allergies in adults in a small Chicago-area sample and decided to explore further.
Because food allergies are most-often linked with children and most study is aimed towards them, far less is understood about adult food allergies. The initial Chicago-area notes came when researchers at Northwestern Medicine noted a 15 percent of adults receiving allergy care at the facility had those allergies come on during adulthood, rather than childhood, in the Chicago-area. They began a new study, which concluded recently and which was presented to the ACAAI.
Most studies into adult-onset food allergies are a decade old or older.
The researchers found that where a 2004 study found that 2.5 percent of adult Americans were allergic to shellfish, their 2017 study found the number was 3.6 percent. Similar rises in tree nut and other food allergies were also noted. Some more than others, in fact, especially for nut-related allergies.
Demographic trends could help explain the change. The study found that Hispanic adults were more at risk for adult-onset food allergies than any other population; about twice as likely as whites when it comes to peanuts, for example. Asians are more likely to develop a shellfish allergy in adulthood. The study's researchers project that this could be due to cultural differences in food preparation for these specific foods.
Environmental factors could also be at work, the researchers note. The research team would like to do a study in the United States that is similarly to one done in Australia, which compared Aussie-born populations of Asians with those who migrated to Australia.