Childhood Food Allergies More Severe and Common than Previously Believed

, nearly six million children—roughly one in twelve children— in the United States are allergic to at least one food.

The foods most commonly connected to a severe reaction included tree nuts and peanuts, shellfish, soy and finned fish.

Researchers performed a nationwide survey of the parents of more than 40,000 children under the age of eighteen.

The parents answered an online questionnaire about allergies concerning on a single child in their household. They reported whether or not the child displayed any signs and symptoms of a food allergy, had ever been diagnosed with an allergy by a doctor, and had ever had a severe allergic reaction to food.

About 8% of the parents reported to having a child who had a food allergy. Of that 8%, roughly 30% of parents said their child was allergic to more than one food.

"Eight percent is a pretty significant amount of kids," said lead study author Dr. Ruchi Gupta, an assistant professor of pediatrics at Northwestern University and a pediatrician at Children's Memorial Hospital in Chicago.

According to the study results:

• 25% of the children were allergic to peanuts
• 21% were allergic to milk
• 17% had an allergy to shellfish
• 13% had allergies to tree nuts
• 10% were allergic to eggs
• 6% had an allergy to finned fish
• 5% were allergic to strawberries
• 5% were allergic to wheat
• Almost 5% had allergies to soy

While the findings can't show whether or not food allergies are on the rise, Gupta reported that she believes they are. "We are seeing a lot more cases,” said Gupta. “We are seeing a lot more in schools than we used to see. It does seem that food allergy is on the rise."

Dr. Susan Schuval, a pediatric allergist at Cohen Children's Medical Center in New Hyde Park, N.Y., agreed that food allergies seem to be becoming more common.

"We are seeing tons and tons of food allergies. There also seems to be an increase from what we've seen in the past," Schuval said.

The researchers were interested not just by how many children reported having allergies, Gupta said, but how many of those allergies were severe enough to cause a child’s airways to become cut off or for their blood pressure to drop.

"One of our big findings was that two in five kids who had allergies had a severe reaction or a life-threatening reaction," Gupta said.

According to the results from the survey, 39% of the children who reported having a food allergy could suffer from a severe or even potentially life-threatening reaction—anaphylaxis—if they ingested something they were allergic to.

The other 61% of the children who reported having food allergies suffered only a mild to moderate reaction—swelling of the lips and face, hives, itching, flushing or an eczema flare.

For some children, food allergies seem to decrease in severity over time. Previous studies have shown that many children outgrow allergies, most commonly to milk, egg, soy and wheat. Not many children report outgrowing peanut, tree nut, fish or shellfish allergies.

Gupta reported, however, that her research showed that severe reactions were more common in older adolescents in the study. This may be because young children with allergies are more likely to be monitored by parents to make sure they stay away from potential allergy triggers, Gupta stated.

Childhood allergies to eggs are particularly disconcerting to most parents, as well as physicians, when it comes to vaccinations. Influenza and measles-mumps-rubella vaccines are routine childhood vaccinations which can present severe threats to children with egg allergies, along with non-routine vaccinations such as yellow fever and typhoid vaccines.

According to the findings, black and Asian children had a higher chance of suffering from a food allergy than Caucasian children, but they were less likely to have their allergies diagnosed by a physician.

Dr. Scott Sicherer, an allergy researcher at the Mount Sinai School of Medicine in New York, said the fact that the parents had not confirmed a suspected allergy with a doctor was a matter which deserved attention.

"Is that because they're not getting the health care they need? Is that because there's not an appropriate amount of concern? I would be worried that the next reaction could be severe and they're not prepared for it,” she stated.

The study also discovered that food allergies were likely to be more severe in boys than girls, among childrentwo years old and younger, and children who suffered from more than one food allergy. Children who lived in regions outside the Midwest were also more likely to have food allergies.

Children from households with an income of less than $50,000, however, had less of a chance of having food allergies, according to the research.

Dr. Clifford Bassett, director of Allergy & Asthma Care of New York and member of the public education committee for the American College of Allergy, Asthma and Immunology, said that it was difficult to figure out what to make of these discrepancies. He stated that more research is needed to determine what might be the associating factors.

While this study has provided a great amount of useful data, there were limitations to this research. The parents who participated in the study supplied their own information about their children, and the diagnoses of the children made by the parents were not confirmed by the children’s doctors.

Currently, the best treatment for children suffering from food allergies is avoidance. An allergic reaction can occur just about anywhere, and most of the time, it’s when a parent least expects it to happen—a family dinner, a birthday party, any place where a child could accidentally ingest something he or she may be allergic to. As such, the researchers advised parents be aware of their child’s allergies as well as what to do in an emergency. They suggested that physicians offer to the parents of children with food allergies a food allergy action plan. They also stressed the necessity of parents to have knowledge of how to administer an epinephrine shot.

"They need to maintain their full alertness out of the home, in the schools and in restaurants," Schuval said.

"What I hope this paper will do is open this awareness to how common (food allergy) is and how severe it can be, and develop policies for schools and sporting events and any activities that kids participate in to make it clear that everybody is looking out for these kids," Gupta reported.

The study is published in the July issue of Pediatrics.