No increase in antibody levels, but food allergies up,suggests a new study.
According to new research published ahead of print in the Journal of Allergy and Clinical Immunology, researchers found no rise of immunoglobulin E (IgE)—food specific—in children’s blood levels from the 1980s up until the 2000’s.
IgE is essentially a blood marker linked with food allergies. After looking at data from around 8,000 kids between the ages of six and 19, analyzing 5,000 stored blood samples and looking for food-specific IgE—researchers discovered there wasn’t a higher prevalence in the number of kids sensitized to allergens such as milk, peanuts, or eggs. The number with antibodies to shrimp went down.
Still, the number of self-reported food allergy rates have risen and food allergy-related hospitalizations and ER visits have went up as well. Study researchers suggest that the higher number of food allergies seen since the 1990s may be attributed to more people recognizing/being more aware of food allergies.
For example, in the past more people might not have eaten specific food because it made them feel sick, although they might not have considered it an allergy. These days, when a child breaks out into hives (for example) after eating a certain food, parents are more likely to suspect it’s from a food allergy.
Many people who have IgE antibodies to specific foods can still eat those foods without problems—so researchers are wondering if there is a changing relationship between food allergy symptoms and IgE. They referenced a recent study that shows how introducing infants to peanuts helped prevent allergies to peanuts, but didn’t lower the rates of IgE to peanuts. In effect, more research needs to be done to figure out why some people with IgE to food will have adverse reactions while others can eat that food with no issue.
Further blood samples and analyzing larger groups of people could help provide further insight into study findings.
“Despite Recent Increases in Reported Food Allergy, Study Finds No Change in Antibody Levels Associated with Food Allergy,” Johns Hopkins Medicine web site, April 25, 2016; http://www.hopkinsmedicine.org/news/media/releases/