By Heidi Kiec
When it comes to preventing a peanut allergy, it might be best to fight fire with fire. Most young children at high risk of developing a peanut allergy may be able to ward off the allergy by consuming peanut protein starting in infancy, according to the results of a recent study.
Peanut allergy is one of the most common food allergies for children, and it is not usually outgrown. Affecting about 1 to 2 percent of American kids, the allergy is the leading cause of anaphylaxis and death due to food allergy.
The study, published in the New England Journal of Medicine, came up with a very important finding for an at-risk population, notes Scott Sicherer, MD, the immediate past chair of the American Academy of Pediatrics (AAP) Section on Allergy and Immunology.
“The conclusion is that there’s enough evidence to seriously consider earlier feeding of peanut protein in infants who fulfill the (high-risk) criteria,” Sicherer says.
The study, conducted in London by Gideon Lack, MB, BCh, observed participants aged 4 to 11 months old and already deemed high risk for developing a peanut allergy, based on an existing egg allergy, severe eczema or both. At the start of the study, 530 infants tested negative for peanut allergy, while 98 participants had a small allergy to peanuts. The participants were randomly assigned to either regularly consume a food containing peanut protein or to avoid peanuts entirely. These feeding patterns continued until the children turned 5 years old.
The half of the study consuming peanut products were fed at least six grams of peanut protein per week, the equivalent of about 24 peanuts, distributed over three or more meals. The recommended food for participants was Bamba, an Israeli puffed corn and peanut butter snack.
The participants who consumed peanut protein were far less likely to be allergic to peanuts at the age of 5. Of the children in the nonallergic group, only 1.9 percent of those fed peanuts had developed an allergy by the end of the study, compared with 13.7 percent of the children in the group avoiding peanuts. The numbers represent an 86 percent relative reduction in the prevalence of peanut allergy.
And among the participants who began the study with a small allergy, only 10.6 percent of those fed peanuts developed a full-fledged allergy by age 5, whereas 35.3 percent of those avoiding peanuts developed the allergy, representing a 70 percent relative reduction in the prevalence of peanut allergy.
Sicherer believes that this study can help change practice. He notes that prior to this study, the prevailing “knee-jerk reflex for infants who already ate egg and got hives was to avoid peanuts, but this is the complete opposite advice. It’s saying, if you have an egg allergy, I want you to eat peanuts to try [to] protect yourself from developing a peanut allergy, if you’re not already allergic.”
Sicherer warns that children in this study had undergone allergy testing to be sure starting peanut protein was done safely and explains that they ate mushy forms of it—similar to baby food—because whole peanuts and peanut butter are choking hazards to infants.
In 2000, the AAP released guidelines recommending that peanuts be withheld until the age of 3 from children at risk of developing the allergy. In 2008, those guidelines were rescinded, citing a lack of evidence that such delays prevent the development of allergies, but no official recommendation on when to introduce peanuts was put forward by the AAP.
Ruchi Gupta, MD, MPH, associate professor of pediatrics at Northwestern University Feinberg School of Medicine and author of The Food Allergy Experience, appreciates having “evidence that shows it could be beneficial if you introduce (peanuts) early. Pediatricians are already counseling families to introduce foods when they are comfortable. This data supports the potential benefit.
Gupta recommends that any parent who is nervous about introducing peanuts into their high-risk infant’s diet should visit an allergist and get proper testing before starting peanuts.
For parents weary of flip-flopping advice on such important health issues, Gupta considers the results “groundbreaking” and goes on to state, “It’s a very strong study and very well done. What it shows is something that most experts around the country will back. There is additional work to be done, but I don’t think these results will be revoked or changed anytime soon.”