If you keep up with the news, you may have recently come across an article suggesting that early introduction of peanut can prevent future peanut allergies. Can this be right? Do we all need to be force feeding our 6-month-old children a spoonful of peanut butter now? Dr. Jay Lieberman, a pediatric allergist at Le Bonheur, shares his insight.

These news articles are reporting results from a recent study in England called the Learning Early About Peanut Allergy (LEAP) study. In this study, the researchers enrolled children 4-11 months of age who were at high risk to develop peanut allergy (they had a history of egg allergy, severe eczema or both). They assigned half of the children to eat peanut at least three times per week up until 5 years of age and the other half they assigned strict peanut avoidance.

For children who had a negative peanut allergy test at baseline, the researchers reported that 14 percent of those children who were told to avoid peanut were found to be allergic to peanut at 5 years of age, while only 2 percent of those in the group who ate peanut weekly were found to be allergic at 5 years of age. This represents an 86 percent relative reduction in the prevalence of peanut allergy by simply having children eat a form of peanut a few times per week.

Of those children that had a positive peanut skin test at baseline, the results were similar, with 35 percent of the avoidance group and 11 percent of the consumption group being allergic to peanuts at 5 years of age (70.0 percent relative reduction in the prevalence of peanut allergy in the consumption group).

So now what do we do? Should every child eat peanut butter early? Should we do this for other allergic foods like shellfish and tree nuts? Should this be done in all children or just those at high-risk for the development of allergy? What happens if the children stop regular ingestion of the peanut; will some of them develop allergy once the peanut is stopped?

For now, these questions cannot definitively be answered. While pediatric guidelines are likely to change in the future based on this new knowledge, there are some things that we can take from this study.

It is reasonable for infants with eczema or other food allergies to have allergy testing done around 5-10 months of age for peanut allergies.

  • If the peanut test is negative, families should likely introduce peanut butter (peanuts are a choking hazard though) at that time.
  • If the allergy testing is positive or questionable, it is reasonable to perform an oral challenge to peanut butter in a doctor’s office (most allergists can do this in a controlled manner). If the infant does not react, then introduction of peanut butter (even with a positive test) is likely warranted.