Incidences of severe food allergies are on the rise in children, with numbers of affected kids jumping 18 percent from 1997 to 2007, CNN reported in early August. About 3 million children younger than 18 had a food or digestive allergy in 2007, the CDC said.
Scientists are still hypothesizing why food allergies would be on the rise, especially in modern countries such as the United States. Possibilities include children not being exposed to enough bacteria and getting kids to eat common allergens like nuts and shellfish at an earlier age.
A study in the Journal of Allergy and Clinical Immunology found that visits to the emergency room at Children's Hospital Boston for allergic reactions more than doubled between 2001 and 2006. Even though this is just one hospital, the discoveries reflect a rise in food allergies found in national reports.
Researchers studied thousands of cases in the emergency department. They didn't rely on the diagnosis given at the time, but made their own determinations about whether and allergic reaction had occurred based on symptoms like hives. This mean that an increase in reactions probably did not have to do with an increased awareness among doctors.
For all adults and children in the U.S., there are 30,000 ER visits because of food allergies each year. But those figures are based on a report that is about 10 years old, and the numbers are likely higher now.
Doctors in other parts of the country have seen an increase in children coming in with severe food allergies as well. Dr. Ronald Ferdman at the Children's Hospital of Los Angeles said his hospital has seen more of these cases.
One common theory is that the Western diet made people more prone to developing allergies and other illnesses. A study in the Proceedings of the National Academy of Sciences compared gut bacteria from 15 children in Florence, Italy, with gut bacteria in 14 children in a rural African village. They found that variety in stomach flora was much different in these two groups.
