Allergies on the Rise

Peanut allergies growing among children

/ Author:  / Reviewed by: Joseph V. Madia, MD

Allergies occur when the body’s immune system reacts abnormally to something in the environment. When these allergic reactions occur in response to a food, the results can be quite dangerous.

Recent studies show that food allergies seem to be increasing in children. With this increase, greater public knowledge and information is required.

Rates Rising

A study published in the Journal of Allergy and Clinical Immunology in 2010 showed that nut allergies among children seem to be on the rise.

The study, led by Scott H. Sicherer, MD, surveyed 13,534 people (5,300 households) via phone in 2008 and compared the results to data collected in 1997. The study examined allergies to peanuts and tree nuts, a category which includes walnuts, almonds and pistachios, among others.

Results showed that 1.4 percent of children under 18 had peanut allergies in 2008, a number that rose from 0.4 percent in 1997.

Furthermore, combined peanut or tree nut allergies rose from 0.6 percent in 1997 to 2.1 percent in 2008. The number of children with tree nut allergies alone was measured at 1.1 percent in 2008, up from 0.2 percent in 1997.

However, these allergies remained constant among adults, with around 1.3 percent reporting peanut and/or tree nut allergies in both 1997 and 2008.

According to Dr. Sicherer, "Our research shows that more than three million Americans report peanut and/or tree nut allergies, representing a significant health burden. The data also emphasize the importance of developing better prevention and treatment strategies."

It is important to consider some limitations of phone-based surveys. These type of studies may be skewed to over represent people of a higher economic class, as those without a phone are not reached. Also, since the study was self-reported, there could be some error in the amount of “true allergies” measured.

Despite these factors, Dr. Sicherer's study does seem to show that nut allergies among U.S. children could be rising, and that more research into these statistics should be completed.

Location, Location, Location

A 2012 study published in Clinical Pediatrics explored a new aspect of this rise in allergies - location.

The study, led by Ruchi Gupta, MD, found that children in large cities with high populations were more likely to have peanut and shellfish allergies than their peers living outside of town.

To obtain this data, 38,465 children under 18 were surveyed and their food allergies mapped by ZIP code.

The results showed that 9.8 percent of children in urban areas have food allergies, compared to 6.2 percent of children in rural areas reporting the same allergies.

The difference in peanut and shellfish allergies were especially marked, with both being twice as prevalent in cities. In cities, 2.8 percent of children had peanut allergies, while the rate was only 1.3 percent in rural communities. For shellfish, the rate of allergies was 2.4 percent in urban areas and 0.8 percent in rural areas.

The study also showed the seriousness of these allergies, as 40 percent of the allergic children had experienced a life-threatening response to eating the sensitive food.

"This shows that environment has an impact on developing food allergies. Similar trends have been seen for related conditions like asthma. The big question is – what in the environment is triggering them? A better understanding of environmental factors will help us with prevention efforts," said Dr. Gupta.

The causes for these location-based differences will surely be examined in future studies.

Staying Safe

While the reasons behind these allergy increases are being explored and debated, the need for greater public knowledge is clear, regardless of the cause.

According to the Centers for Disease Control and Prevention (CDC), symptoms of food allergies can range in severity and include stomach cramps, hives, vomiting and tingling in the mouth.

Anaphylaxis is a severe response and can cause intense swelling of the tongue and throat and problems breathing. An allergic reaction like this can lead to death and require quick treatment with a drug called epinephrine. Less severe reactions can be treated with over-the-counter antihistamines.

By far the best way to avoid allergic reactions is to avoid the foods that trigger them. This is an issue that often comes up as children with food allergies enter school.

The CDC reports that “16 to 18 percent of children with food allergies have had allergic reactions to accidental ingestion of food allergens while in school” and perhaps more worrisome, “25 percent of anaphylaxis reactions in schools occur among students without a previous food allergy diagnosis.”

Because of this, schools need to be prepared to manage emergency allergy situations effectively and quickly, especially as more children are affected. 

With knowledge of symptoms, awareness of food ingredients and preparation for emergencies, schools and parents can keep kids safe and healthy in the face of increasing food allergy rates.

Reviewed by: 
Review Date: 
August 6, 2012